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Gilead Sciences (GILD 0.23%)
Q4 2023 Earnings Call
Feb 06, 2024, 5:00 p.m. ET

Contents:

  • Prepared Remarks
  • Questions and Answers
  • Call Participants

Prepared Remarks:


Operator

Good afternoon. Thank you for attending the fourth-quarter and full-year 2023 Gilead Sciences earning conference call. My name is Victoria and I'll be your moderator today. All lines will be muted during the presentation portion of the call with the opportunity for questions and answers at the end.

I would now like to pass the conference over to your host, Jacquie Ross. Thank you. You may proceed, Jacquie.

Jacquie Ross -- Vice President, Investor Relations

Thank you, operator, and good afternoon, everyone. Just after market close today, we issued a press release with earnings results for the fourth quarter and full year of 2023. The press release, slides, and supplementary data are available on the investors section of our website at gilead.com. The speakers on today's call will be our chairman and chief executive officer, Daniel O'Day; our chief commercial officer, Johanna Mercier; our chief medical officer, Merdad Parsey; and our chief financial officer, Andrew Dickinson.

After that, we'll open the call to Q&A, where the team will be joined by Cindy Perettie, the executive vice president of Kite. Before we get started, let me remind you that we will be making forward-looking statements, including those related to Gilead's business, financial condition and results of operations; plans and expectations with respect to products, product candidates, corporate strategy, business and operations, financial projections and the use of capital; and 2024 financial guidance, all of which involve certain assumptions, risks, and uncertainties that are beyond our control and could cause actual results to differ materially from these statements. A description of these risks can be found in the earnings press release and our latest SEC disclosure documents. All forward-looking statements are based on information currently available to Gilead, and Gilead assumes no obligation to update any such forward-looking statements.

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Non-GAAP financial measures will be used to help you understand the company's underlying business performance. The GAAP to non-GAAP reconciliations are provided in the earnings press release, in our supplementary data sheet, as well as on the Gilead website. With that, I'll turn the call over to Dan.

Dan O'Day -- Chairman and Chief Executive Officer

Thank you, Jacquie, and good afternoon, everyone. The team and I are pleased you could join us today as we share the details of our full-year and fourth-quarter performance and the latest on our clinical portfolio. Starting with our full-year performance, 2023 was a strong year for Gilead, with 7% growth in product sales, excluding Veklury, driven by HIV and oncology. HIV grew by almost $1 billion, with Biktarvy sales growing 14% to almost $12 billion and increasing its market share in the U.S.

to 48%. oncology grew 37% to almost $3 billion, an increase of almost $800 million in just one year. This growth was split evenly between our Kite cell therapies and Trodelvy. Veklury for COVID-19 contributed $2.2 billion in 2023, ahead of our expectations, but down year over year, as expected, given the evolution of the pandemic.

In the last two years combined, Gilead's base business has grown approximately $3.3 billion, or more than 7% annually, largely offsetting the decline in Veklury revenues over the same period. The consistent growth in our base business gives us a strong foundation as we continue into 2024 and look to deliver on our broad clinical portfolio. This is a catalyst-rich phase for Gilead with more than 20 updates this year and many more to come beyond 2024. Starting with oncology, we expect at least 12 further updates by the end of 2024.

These include phase 3 updates for Trodelvy in bladder and triple-negative breast cancer, and results from the pivotal phase 2 iMMagine-1 study for anito-cel in multiple myeloma, for which we saw encouraging phase 1 data at the American Society of Hematology meeting in December. Also in cell therapy, we are very pleased to have shortened our manufacturing time for Yescarta by another two days in the U.S., reinforcing our industry-leading median turnaround time, which is now at an anticipated 14 days. As you know, we did not reach the primary endpoint for EVOKE-01, our phase 3 trial for second-line metastatic non-small cell lung cancer. Merdad will go into detail on this later, but while we did not see the outcome we hoped for, the data are encouraging on a number of levels, namely: a numerical improvement in overall survival favoring Trodelvy, including in both squamous and non-squamous tumors; a safety profile consistent with our product label that could continue to differentiate Trodelvy versus other TROP2 ADCs; and, while not statistically powered, a potential benefit for a pre-specified sub-population that saw more than three months' median overall improvement.

3 The team is evaluating next steps given the data and the significant unmet need, and we look forward to discussing the data with regulators. Based on the totality of the results in both EVOKE-02 and EVOKE-01, we are confident in Trodelvy's potential in patients with metastatic non-small cell lung cancer, including in earlier lines of therapy. In virology, we are looking forward to a very important year for our HIV portfolio. Among the multiple updates we are expecting are the phase 3 data for lenacapavir in HIV prevention and at least eight updates from our HIV treatment program.

These are milestones that could bring us closer to our goal of helping to end the HIV epidemic, building on Gilead's decades of leadership in HIV. In COVID-19, today we are announcing that our phase 3 trial, OAKTREE, evaluating obeldesivir did not meet its primary endpoint. We conducted this study to explore whether obeldesivir could address the public health need that existed with COVID-19 for standard-risk patients. Again, Merdad will share details later, but essentially, because of the way things have evolved, the standard-risk population is now better able to fight COVID-19 without antiviral therapy.

This made it more difficult for obeldesivir to show a benefit compared to the placebo. We know that the world needs to be equipped for other viruses, and the broad antiviral activity of obeldesivir shown preclinically means it has potential for other viral infections. The updates we are expecting in 2024 have the potential to unlock multiple opportunities across virology and oncology. With a broad portfolio where the risk is balanced, we look forward to following the science and continuing to make a positive impact for patients and communities.

Gilead has set an ambitious goal of delivering at least 10 transformative therapies by 2030, and we are driving confidently to that goal. Before I hand over to the team for their updates, I'll move to Slide 6 and recap that we executed well in 2023 and achieved all the remaining targeted goals that we expected to in the fourth quarter. We'll share our 2024 milestones later in the presentation, but it's clear that it's going to be a very busy year for Gilead. I'd like to thank the teams for their work in bringing us to this important catalyst-rich phase for the company, and for the strong commercial performance that gives us a firm foundation on which to build.

With that, I will hand it over to Johanna.

Johanna Mercier -- Chief Commercial Officer

Thanks, Dan, and good afternoon, everyone. Beginning on Slide 8, total product sales for the full year were at the high end of our guidance range at $26.9 billion, reflecting solid base business growth, with total product sales, excluding Veklury, up 7% year over year to $24.7 billion. This was almost entirely offset by the expected decline in Veklury sales. For the full year, Veklury sales were $2.2 billion, reflecting the uptick in hospitalizations at the end of 2023, though still below levels seen in 2022.

Turning to the fourth quarter on Slide 9, total product sales were $7.1 billion, down 4% year over year. Our base business sales were roughly flat year over year at $6.3 billion, primarily driven by higher oncology sales, offset by lower HIV sales due to changes in channel mix that resulted in lower average realized price, in addition to the expected decline of our portfolio of non-promoted products. Moving to Slide 10, our HIV business delivered very strong results for the full year, up 6% year over year to $18.2 billion and contributing almost $1 billion in base business growth, primarily driven by demand, as well as higher average realized price due to channel mix and inventory dynamics. More specifically, almost half of the full-year HIV growth was driven by higher demand, most notably by Biktarvy which delivered solid double-digit year-over-year growth of 14%, with annualized revenues now more than $12 billion.

Already the clear market leader, Biktarvy continues to demonstrate impressive share gains, growing almost 3% year over year in the fourth quarter of 2023, to approximately 48% share in the U.S. This growth, once again, outpaced all other branded regimens for HIV treatment, and represented the 22nd quarter of consecutive year-over-year share gains. For the fourth quarter, as highlighted on Slide 11, HIV sales of $4.7 billion reflected strong demand in line with our expectations. On a year-over-year basis, this was offset by lower average realized price due to channel mix that was notably favorable in the fourth quarter of 2022, and resulted in a decline of 2%.

Sequentially, sales were up 1%, similarly driven by strong demand as well as favorable inventory dynamics, partially offset by lower average realized price due to channel mix. As we have noted previously, the pricing tailwinds we saw in the second half of 2022 and the first half of 2023 are not expected to repeat and will make year-over-year comparisons more challenging in the immediate term, as we saw in the fourth quarter. As a reminder, quarterly HIV growth is, in general, significantly more variable and less indicative of overall trends than the full year, particularly as certain quarterly pricing and inventory dynamics tend to normalize over the course of the year. Factors include, first, gross-to-net adjustments which can be difficult to forecast due to the lag between product sales and claim payments that frequently occur in different quarters; second, the timing of bulk government purchases which contribute to overall demand but can have a significant, negative impact on pricing in the quarter in which they occur.

For example, certain discounted government segments are unpredictable in terms of bulk order timing, and this impacts overall average realized price; and finally, the inventory build by subchannel wholesalers and customers that typically occurs toward the end of the year. Historically, this happens in the fourth quarter. In 2023, we saw the build start in the third quarter and continue, albeit to a lesser extent relative to prior years, into the fourth quarter. Overall, despite these quarterly variables, we remain confident that overall demand trends are strong and unchanged.

With our HIV treatment market share above 70% in the U.S. and above 40% in PrEP, Gilead remains well positioned to continue delivering demand-driven growth. For 2024, we expect HIV sales to grow approximately 4%, reflecting annual treatment demand growth of 2% to 3%; Biktarvy market share gains; and continued double-digit growth in demand for HIV prevention. In terms of quarterly HIV revenue, keep in mind that the first quarter is always impacted by the reset of patient copays and deductibles.

Additionally, we've historically seen inventory buildup in the fourth quarter that has led to notable draw-downs by wholesalers in the first quarter. In the first quarter of 2023, this contributed to HIV sales declining 12% sequentially, and we expect a similar decline in the 10% to 12% range for the first quarter of 2024. The continued strong performance of both Biktarvy and Descovy for PrEP are shown on Slide 12. Overall, Gilead's leadership in HIV is unmatched, with a solid commercial portfolio and robust pipeline of potentially best-in-class regimens to serve the daily oral, long-acting oral, and long-acting injectable markets.

And I can share that we are off to a strong start in terms of HIV demand, which gives us confidence in our full-year expectations for 2024. Moving to liver disease portfolio on Slide 13, sales of $2.8 billion for the full year highlight the consistently strong and stable contribution from our liver disease portfolio. In the fourth quarter, sales were $691 million, flat year over year and down 2% sequentially, primarily driven by unfavorable pricing dynamics, offset by higher HCV market share and our efforts to increase linkage to care, in addition to growing HDV demand in new and existing European geographies. In HCV, we continue to reinforce Gilead's leadership with market share of over 60% in the U.S.

and over 50% in Europe. While we continue to expect the rate of HCV new starts to trend downwards over time given the curative nature of our medicines, demand growth in both HDV and HBV is largely offsetting that headwind. Onto Slide 14, Veklury sales continue to be highly variable with the fourth quarter down 28% year over year, though up 13% sequentially due to higher COVID-related hospitalizations in the fourth quarter. For the full year, Veklury sales of $2.2 billion exceeded the expectations we set out at the beginning of 2023.

Turning to Slide 15. Our oncology business has achieved an annualized run rate that now exceeds $3 billion with strong fourth-quarter sales of $765 million, up 24% year over year. In just three years, Trodelvy revenue has grown to more than a billion dollars, and we continue to see strong growth across our approved indications. And in cell therapy, sales approached $2 billion in 2023, and Kite remains firmly established as the leading provider of CAR T-cell therapies globally.

Looking more closely at Trodelvy on Slide 16, sales for the full year were $1.1 billion, up 56% year over year. For the fourth quarter, sales were $299 million, up 53% year over year and 5% sequentially. With over 30,000 patients treated to date, Trodelvy's solid demand trends continue to reinforce its robust clinical profile as the only TROP2-directed antibody-drug conjugate approved and available in multiple tumor types. Awareness and utilization continue to increase, driving notable share gains.

In second-line metastatic triple-negative breast cancer, approximately one-third of patients are receiving Trodelvy, reinforcing its position as the leading regimen across the U.S. and other major markets. In pre-treated HR+/HER2- metastatic breast cancer, we're encouraged to see share growth overall, driven by increasing adoption in the IHC0 setting as well as continued use in HER2-low. Additionally, we look forward to potentially making Trodelvy more broadly available in metastatic bladder cancer.

Data from the confirmatory phase 3 TROPiCS-04 study in the first half of the year could enable global filings and subsequent launches, as well as potentially drive adoption in the U.S., altogether expanding Trodelvy's potential reach to nearly 25,000 second-line-plus patients with metastatic bladder cancer. Turning to Slide 17, and on behalf of Cindy and the Kite team, cell therapy sales of $1.9 billion in 2023 grew 28% from 2022, driven by impressive growth, particularly outside the U.S. as we expanded our network of authorized treatment centers, and secured reimbursement following recent approvals. In the fourth quarter, cell therapy product sales were $466 million, up 11% year over year and down 4% sequentially, with strong growth in both Yescarta and Tecartus in Europe and other international markets, offset in part by near-term headwinds for Yescarta in the U.S.

from both in-class and out-of-class competition. As previously discussed, CAR T class share of eligible second-line plus large B-cell lymphoma patients remains at roughly 15% in the U.S. as growth continues to be slower than anticipated despite the compelling clinical data that suggests these therapies are potentially transformative for many patients. In Europe and other markets, CAR T class share in this same second-line plus setting continues to be stronger at approximately 30%.

Following a restructuring in November, the Kite team has been focused on extending the reach of cell therapies from primarily academic medical centers to community practices, especially in the U.S. In late 2023, we established partnerships with leading community networks, which include over 1,750 physicians nationally. We are certifying affiliated practices to become authorized treatment centers to provide Kite cell therapies. So far, we've made notable headway across centers in the southeast United States, for example, that operate over 40 locations to serve cancer patients.

We expect to see the initial impact of these initiatives in mid-2024. In the meantime, we expect our cell therapy business to be flat to slightly up in the first quarter of 2024 compared to the fourth quarter of 2023. Importantly, alongside our 96% reliability rate, we're also thrilled to share that we have shortened our manufacturing time in the U.S. by two days for Yescarta, bringing our anticipated median turnaround time to 14 days.

This further extends our industry leadership in terms of manufacturing, and the Kite team continues to innovate in this critical element of the cell therapy business. We look forward to inviting you to visit one of our manufacturing facilities later this quarter during an analyst and investor event. In conclusion, I would like to thank our teams for a strong 2023 performance and setting up such great momentum for continued growth in 2024. The team is excited to continue to make our medicines accessible to all those who can benefit from them.

And with that, I'll hand the call over to Merdad.

Merdad Parsey -- Chief Medical Officer

Thank you, Johanna. We have had a busy start to 2024, and I'll begin by discussing the results of our EVOKE-01 study in second-line plus metastatic non-small cell lung cancer and our phase 3 OAKTREE study of obeldesivir in standard-risk, non-hospitalized patients with COVID-19. While we are disappointed that these studies did not meet their primary endpoints, we are also encouraged by what we are learning from the data to inform our clinical programs and support our commitment to deliver innovative new therapies for patients. Let me cover each of these readouts in turn.

First, on Slide 19, our phase 3 study of Trodelvy in 2L+ metastatic non-small cell lung cancer, EVOKE-01, missed its primary endpoint of overall survival in this hard-to-treat setting. We plan to share the detailed data at the earliest opportunity. In the meantime, we'd like to highlight what we believe to be important set of observations from EVOKE-01 that give us continued confidence in Trodelvy as a pipeline-in-a product and its potential to benefit some patients with lung cancer. We saw a numerical improvement favoring Trodelvy, including in patients with both squamous and non-squamous histologies.

This is encouraging for our ongoing phase 3 EVOKE-03 first-line trial evaluating Trodelvy in PD-L1 high patients, in combination with pembrolizumab. Importantly, Trodelvy continues to demonstrate a potentially differentiated safety, efficacy, and tolerability profile, with an adverse event profile that is consistent with our label. Further, Trodelvy achieved more than three months of improvement in median overall survival in a pre-specified subgroup of patients non-responsive to their prior anti-PD-(L)1 therapy. This subgroup is defined as those who achieved stable disease or progressive disease as their best outcome to last prior I/O therapy, and represented more than 60% of the trial population.

This analysis was not alpha-controlled for formal statistical testing, and we are continuing to analyze these data. We will discuss these data with regulators and KOLs to determine the best path forward. As a reminder, we required all patients to have received prior I/O therapy, regardless of driver mutation status, and responsiveness to prior I/O was a stratification factor. Additional analyses, including TROP2 expression, are ongoing.

We will share these data as quickly as possible. Based on these observations and the data from the ongoing EVOKE-02 study, we remain confident in Trodelvy's potential in patients with metastatic non-small cell lung cancer. For now, given these findings, we currently do not plan changes to our phase 3 EVOKE-03 study that is enrolling as expected. Moving to Slide 20, our novel twice-daily, oral antiviral, obeldesivir, did not demonstrate statistically significant symptom relief in standard-risk, non-hospitalized patients with COVID-19 in our phase 3 OAKTREE trial.

Obeldesivir was well-tolerated in this large study population, and we will share the data at a future medical meeting. Overall, the OAKTREE results reflect the decreasing severity and duration of COVID-19 symptoms observed in standard-risk patients, driven by the evolution of variants and improved immunity to COVID-19 in our trial population. The time to symptom alleviation in untreated, standard-risk patients is now less than a week, as compared to almost two weeks at the peak of the pandemic. As a result, it was challenging for obeldesivir to show a benefit in the standard-risk population.

We continue to assess whether obeldesivir could address other viral infections given the broad antiviral activity that we have observed in preclinical data. Moving to another clinical update in oncology, the phase 3 ENHANCE-3 trial evaluating magrolimab in front-line unfit AML has been discontinued based on a futility analysis and a higher observed incidence of Grade 5 serious adverse events. Following the discontinuation of ENHANCE and ENHANCE-2 last year, we do not plan further development of magrolimab in hematologic cancers. Wrapping up on clinical updates, I want to thank all those who were involved with EVOKE-01, OAKTREE and ENHANCE-3.

Every trial adds important advancements in our understanding of the treatment of these diseases and will inform our future development plans. We look forward to sharing more on that in due course. Transitioning to our HIV program on Slide 21, we expect the phase 3 readout of PURPOSE-1 evaluating lenacapavir for HIV prevention later this year. Along with PURPOSE-2, expected in late 2024 or early 2025, PURPOSE-1 forms the basis of our potential regulatory filing.

We continue to target our first approval for lenacapavir for prevention as early as late 2025, potentially making lenacapavir the first twice-yearly dosing regimen available for PrEP. Looking at our HIV program more broadly, you can see we will be sharing at least nine updates this year across our next-generation daily, weekly, three-monthly, and twice-yearly programs, all based on lenacapavir, our novel, first-in-class long-acting capsid inhibitor. We are excited to have over 75 presentations at CROI this year across Gilead-led and -supported studies. Among them, some notable updates from our treatment pipeline include encouraging data from our phase 2 ARTISTRY-1 trial evaluating our lenacapavir and bictegravir once-daily oral.

We are exploring this combination as a potential additional option for virologically suppressed people living with HIV; phase 1 data on GS-1720, our once-weekly oral integrase inhibitor; and phase 2 data on lenacapavir plus islatravir, our once-weekly oral combination in development with Merck. In the second half of this year, we look forward to providing an update on the phase 2 trial evaluating lenacapavir plus bNAbs as a twice-yearly regimen. Turning to cell therapy on Slide 22, you may have seen that the FDA recently proposed safety label changes for all approved CD19 and BCMA CAR T-cell therapies, including Yescarta and Tecartus. There is no change to our confidence in the benefit-risk profile of Yescarta and Tecartus.

Based on analysis of our Global Safety Database, with over 16,800 patients treated with Yescarta, there has been no causal link established between Yescarta and those reported to the FDA public safety dashboard. Additionally, no cases of T-cell malignancies have been reported with Tecartus. In the fourth quarter of last year, we presented 26 abstracts at the American Society of Hematology meeting in December, showing that Yescarta and Tecartus continue to generate some of the longest follow-up and most robust datasets for cell therapies with the potential to transform patient lives. Also at ASH, our partner, Arcellx, presented impressive, updated data from the phase 1 trial evaluating anito-cel in 38 patients with relapsed or refractory multiple myeloma.

At a median follow-up of 26.5 months, median progression-free survival was not yet reached, despite 70% of patients having one or more high-risk prognosis factors. Given its potentially differentiated safety profile, with notably no delayed neurotoxicity to date, including parkinsonism, anito-cel has the potential to become the best-in-class BCMA CAR T. We look forward to sharing an update from the pivotal phase 2 iMMagine-1 study and initiating an earlier-line multiple myeloma trial later this year. In terms of manufacturing, while Kite is already the clear leader, we're pleased to highlight that the FDA approved our updated process that reduces the turnaround time for Yescarta in the U.S.

from 16 days down to 14 days. This further extends our leadership in cell therapy, and we continue to identify additional opportunities to reliably bring these much-needed therapies to more patients as quickly as possible. Beyond manufacturing, we have eight ongoing cell therapy trials, of which four are evaluating new indications and four are exploring earlier lines of therapy. As we formally wrap up 2023, on Slide 23, I would like to acknowledge the work of our clinical teams who executed on our ambitious and broad portfolio that extends far beyond the list shown, including the advancement of eight new assets to the clinic; the delivery of 15 late-breaking oral presentations at major clinical congresses; and the initiation of three new phase 3 programs.

For 2024, our targeted milestones laid out on Slide 24 include an update on ASCENT-03 in first-line PD-L1 negative metastatic triple-negative breast cancer; an update on TROPiCS-04 assessing overall survival in second-line metastatic or locally advanced bladder cancer; and an update on our phase 3 PURPOSE-1 trial assessing lenacapavir in HIV prevention, as previously highlighted. We are also looking forward to the start of phase 3 trials for Trodelvy in endometrial cancer, and the ARTISTRY trials evaluating lenacapavir and bictegravir oral combination for HIV treatment. Our commitment to develop innovative new therapeutic options is unchanged and we are confident that we will make progress on that commitment in 2024. And now, I'll hand the call over to Andy.

Andy Dickinson -- Chief Financial Officer

Thank you Merdad, and good afternoon, everyone. Starting on Slide 26, we closed the year with total product sales of $26.9 billion, at the top end of our guidance range due to a strong contribution from Veklury. For the full year, total product sales, excluding Veklury, grew 7% driven by growth in both HIV and oncology. HIV increased 6% year over year, driven by Biktarvy, which grew 14% from 2022 to $11.8 billion.

And oncology grew to $2.9 billion for the full year, an increase of $792 million, or 37% from 2022. Altogether, total product sales, excluding Veklury, were $24.7 billion – modestly below the lower end of our full-year guidance range largely due to quarterly pricing variability in HIV in the fourth quarter. Importantly, HIV volumes were in line with our expectations, and we are confident in our full-year revenue growth expectations for HIV in 2024. Veklury revenue of $2.2 billion exceeded our guidance of approximately $1.9 billion, and reflected higher hospitalization rates in the latter part of 2023.

Compared to 2022, full-year Veklury revenue declined as expected and represented a headwind of more than $1.7 billion to total product sales. This was largely offset by almost $1.7 billion in growth from our base business, resulting in roughly flat total product sales year over year. On Slide 27, our non-GAAP results were largely as expected, including gross margin and operating expenses, notably R&D which showed disciplined moderation as we progressed through 2023. Non-GAAP EPS was $6.72 and within our guidance range despite the incremental $0.10 of acquired IPR&D associated with the Arcellx and Compugen partnerships that we announced following our guidance revision in November 2023.

A quick note that our GAAP results were impacted by some restructuring expenses, primarily related to our manufacturing strategy and our activities at Kite. As we discussed in the later part of 2023, we have been taking steps to evolve our business model and expense structure to set us up for a strong 2024. As a result, our GAAP results reflect approximately $500 million of associated expenses in 2023, or $0.40 per share, and contributed to GAAP EPS of $4.40 for the full year. Moving to our fourth-quarter results starting on Slide 28, total product sales, excluding Veklury, were $6.3 billion.

Including Veklury, total product sales of $7.1 billion were down 4% from the same quarter in 2022. As expected, Veklury sales decreased year over year due to lower rates of COVID-19-related hospitalizations. On Slide 29, you can see that on a non-GAAP basis product gross margin was 86%, down 66 basis points from the prior year; R&D expenses were $1.5 billion, down 6% year over year; acquired IPR&D was $347 million, reflecting payments related to our collaborations with Arcellx, Assembly Biosciences, and Compugen and our XinThera acquisition; SG&A was $1.6 billion, down 21% year over year, primarily related to the 2022 charge for the termination of the Everest collaboration that did not repeat in 2023. Excluding this 2022 charge, non-GAAP SG&A was down 1%; operating margin was 39%, up from 37% in the fourth quarter of 2022; and effective tax rate in the fourth quarter was 17%, flat compared to the prior year.

Overall, our non-GAAP diluted earnings per share was $1.72 in the fourth quarter, compared to $1.67 in the fourth quarter of 2022. I'll move now to Slide 30 and our guidance which assumes a generally stable macro environment including FX at current rates. For the full-year 2024, we expect total product sales in the range of $27.1 to $27.5 billion. We expect total product sales, excluding Veklury, in the range of $25.8 to $26.2 billion, representing growth of 4% to 6% for our base business year over year.

Within total product sales, and as Johanna discussed, we expect HIV revenue to grow approximately 4%, and we expect Veklury sales of approximately $1.3 billion although, as always, we caution you that Veklury sales remain highly variable depending on hospitalization rates. We do not expect to update our Veklury guidance until our third-quarter earnings call, absent a very clear trend in COVID-19 infections. Moving to the rest of the P&L, and on a non-GAAP basis, we expect product gross margin to range between 85% and 86%, modestly lower than the 86.1% reported in 2023 due to the growing contribution from our oncology portfolio. We expect R&D to grow by a low to mid-single-digit percentage compared to 2023, highlighting the substantial moderation in expense growth as we approach a steadier state of active phase 3 programs.

We expect acquired IPR&D to be approximately $350 million. Consistent with our approach in 2023, we will highlight incremental acquired IPR&D expenses as we announce new transactions and update our guidance each quarter. And we expect SG&A to decline by a mid-single-digit percentage compared to 2023. Excluding the $525 million legal settlement in 2023, we expect SG&A to grow in the low to mid-single-digit percentage range compared to SG&A of $5.5 billion in 2023, excluding this settlement.

As a result, we expect our operating income for 2024 to be between $11.2 billion and $11.7 billion; we expect our effective tax rate to be approximately 19%; and finally, we expect our non-GAAP non-diluted EPS to be between $6.85 and $7.25 for the full year, and GAAP diluted EPS to be between $5.15 and $5.55. As a reminder, for the first quarter of 2024, we expect HIV to decline sequentially in the 10% to 12% range from Q4 2023, similar to what we saw in the first quarter of 2023; and cell therapy to be flat to slightly up from Q4 of 2023. Moving to capital allocation on Slide 31, our priorities have not changed. In 2023, we returned $4.8 billion to our shareholders.

This included $3.8 billion in dividend payments and $1 billion in share repurchases. Fourth-quarter share repurchases were $150 million. For 2024, we announced today a 2.7% increase in our quarterly cash dividend, to $0.77 per share, and we remain committed to growing our dividend over time, in line with earnings growth. You can also expect to see continued investments in our business, both internally and externally, through select partnerships and business development transactions.

Finally, we will continue to utilize share repurchases to offset equity dilution, as well as additional repurchases on an opportunistic basis. With that, I'll invite the operator to begin the Q&A.

Questions & Answers:


Operator

Of course, Andrew. We will now begin the question-and-answer session. [Operator instructions] Our first question comes from a line of Tyler Van Buren with TD Cowen. Your line is now open.

Tyler Van Buren -- TD Cowen -- Analyst

Hey, guys, good afternoon. Regarding the 2024 product sales guidance, I understand you guys are guiding to near 900 million sales drop-off year over year for Veklury, but the guidance ex Veklury looks to be a 5% year-over-year growth at the midpoint versus 7% for this year. So, what do you view as some of the levers to expect Veklury product sales guidance in '24 where we could see upside?

Dan O'Day -- Chairman and Chief Executive Officer

Thanks, Tyler. Welcome. Let's have Andy start, please. Thanks.

Andy Dickinson -- Chief Financial Officer

Hey, Tyler, it's Andy. Thanks for the question. You're absolutely right, our product sales guidance for products excluding Veklury implies 4% to 6% growth year over year, again continuing the trend of strong growth that you've seen over the last two years. I'd also highlight that it implies a substantial moderation of our -- of our operating expense growth, which is an important piece of the puzzle that we spent a lot of time talking about.

To your question specifically on product growth, the growth drivers for 2024 are the same as the growth drivers last year. You continue to see strong growth in our HIV business. As you see in the quarter, you really need to focus on the full year for the HIV to see the growth trends, and we saw another year of very strong growth across our HIV business for the full year in '23. We expect the same thing in '24.

And you heard on the call that we were expecting at least 4% growth for the HIV business next year. And then, of course, the cell therapy business and -- and Trodelvy are expected to continue to grow as well. So, those are the key growth drivers. We look forward to updating you throughout the year, but we're excited about the setup as we move into 2024.

Jacquie Ross -- Vice President, Investor Relations

Victoria, our next question, please.

Operator

Thank you so much. Of course. Thank you so much for your question. Our next question comes from the line of Salveen Richter with Goldman Sachs.

Your line is now open.

Salveen Richter -- Goldman Sachs -- Analyst

Good afternoon. Thanks for taking my question. On business development, you have noted the potential for a $5 billion to $6 billion deal in oncology or I&I. Where are you seeing the greatest opportunity to leverage your current clinical and commercial infrastructure? Thank you.

Dan O'Day -- Chairman and Chief Executive Officer

Great. Thanks, Salveen. This is Dan. Maybe I'll start and then ask others to add, but appreciate the -- the question.

I think just to reinforce our M&A strategy, I mean nothing has changed from a business to development perspective. And particularly, that's against the context of the background of nearly doubling our clinical trials underway over the past four years, multiple late-stage results. As you know, we're expecting more than 20 results still this year, and against the backdrop of no significant patent expirations, in our business until early parts of the next decade. So, I think we'll continue to be opportunistic about pursuing business development in the three areas that we are focused on, which is obviously virology, oncology, and inflammation, will be driven by the science. We continue to articulate that, you know, building our -- our late research early development pipeline is probably one of our biggest focuses and will continue to look at later-stage deals as they fit into our portfolio and our range. It might also be important to note that, you know, we are back to pre-Immunomedics levels now relative to our leverage ratios.

And -- and so, we're comfortable with our ability to put capital to work. But nothing has changed, and we feel we have everything within Gilead right now to achieve our ambitions over the second half of this decade.

Jacquie Ross -- Vice President, Investor Relations

Victoria, may we have our next question, please.

Operator

Of course. The next question comes from the line of Carter Gould with Barclays. Your line is now open.

Leon Wang -- Barclays -- Analyst

Hi, this is Leon Wang on for Carter. Thanks for taking my question. So, at this point, what conviction do you have anito-cel will differentiate neurotox or Parkinsonian-ism versus your competitors? And if the lack of neurotox data recapitulate later this year, would that be derisking in your view, and how important would that be in the market? Thank you.

Dan O'Day -- Chairman and Chief Executive Officer

Thank you, Leon. So, we've got Cindy Perettie here to handle that. Thanks.

Cindy Perettie -- Executive Vice President, Kite

Thank you. Thank you for the question. I think with the anito-cel data, we expect to complete the enrollment of our iMMagine-1 study this year, where we would have been 100 patients worth of data. And obviously, we're going to continue to look for safety signals, neurotoxic as you suggested, but to date, we have not observed any. Your second part of that question was do we see that as a differentiator, and I would definitely see that as a differentiator in the marketplace if we were to come forward with a differentiated safety profile.

I think the other component to remind you of is we also believe it's possible to have a differentiated efficacy profile. And today, based on the D domain kind of transduction efficiency, we're able to use half the dose that we're seeing with our competitors, and that could play both with safety and efficacy. Thank you.

Jacquie Ross -- Vice President, Investor Relations

Great. Victoria, ready for our next question, please.

Operator

Of course. Our next question comes from the line of Terence Flynn with Morgan Stanley. Your line is now open.

Terence Flynn -- Morgan Stanley -- Analyst

Thanks so much for taking the question. Was just wondering if you could speak to your confidence level in Trodelvy in the front-line non-small cell lung trial setting here given the EVOKE-01 data, and if you're considering any potential changes to that -- that front-line trial as a result. Thank you.

Merdad Parsey -- Chief Medical Officer

Hi, Terence, this is Merdad. You know, I think when we have looked at the data so far, and we're looking forward to sharing it with everyone as quickly as we can, probably one of the most important things in that data set that confirmed where we were before is that we have not seen a difference in response rates between squamous cell carcinoma and non-squamous cell carcinoma. I think that was a bit of an overhang in the fall. And as we had mentioned earlier, we had not seen that to date and that has been bolstered by the results of EVOKE-01. So, we do think that that increases our confidence that we don't need to think about -- look at that.

Now, there are other analyses we need to do to make sure that there are other -- there are other predictors of response or not. And we'll be doing that and we'll be sharing that over time. But right now, our overall confidence in Trodelvy , broadly speaking, remains very high. We have three approvals, and we have a broad development program, against which we are executing really well. We continue to have additional trials that will read out this year. And in phase 3, specifically the TROPiCS-04 study that we'll be looking at the bladder cancer confirmation study with, hopefully, an OS signal.

That study could actually give us -- beyond confirmatory trial in the U.S., it allows us to open conversations with regulators outside the U.S. And then, we have promised an update on ASCENT-03 in breast cancer, which we also think will broaden that. And then, we now have a number of trials going on in a variety of indications including ones we've mentioned in, for example, endometrial cancer. So, overall, what we've seen EVOKE-01 and we're looking forward to sharing with you really maintains our level of enthusiasm about Trodelvy's long-term potential from an efficacy and safety standpoint across the board. And we have no plans to change at EVOKE-03 at this time.

Jacquie Ross -- Vice President, Investor Relations

Victoria, next question, please.

Operator

Our next question comes from the line of -- yes, ma'am. Our next question comes from the line of Umer Raffat with Evercore. Your line is now open.

Umer Raffat -- Evercore ISI -- Analyst

Hi, guys. Thanks for taking my question. Look, it's very well understood for folks in biopharma community that no one can truly understand the full safety profile of any new drug based on phase 1 data. And -- but this point has a lot of implications for your TAF litigation, obviously. So, my question is, in a scenario where the Supreme Court takes up your petition, would that potentially be a venue where you could prove the level of evidence that's actually needed to make a decision on exception to duty and the type of decisions to make?

Dan O'Day -- Chairman and Chief Executive Officer

Right, Andy, can you take this one?

Andy Dickinson -- Chief Financial Officer

Hi, yeah, thanks for the question. Yes, of course. I mean in front of the Supreme Court, just like the -- the appellate court, we'll be able to present the facts and -- and our arguments as you expect. If you look at some of the briefing documents in the appellate court, I think they spell that out very clearly in terms of the -- you know, what happened over time with the -- with the development of TAF and what we knew at different points in time.

And that would be available, as you'd expect, not only to the appellate court, but to the Supreme Court. And of course, those same -- those same facts would be presented at any trial if we ever get to that point. One other update on the TAF litigation, again, nothing's changed from our perspective. We continue to have a lot of confidence.

The one update I can provide is that the -- one of the very first trial in the federal court has been dismissed as of yesterday, I believe. So, it now looks like -- and again, this is consistent, as you know, with the thousands of other cases. I think it's now over 5,300 cases that have been dismissed by the courts, over 4,300 in the -- in the California state courts, and over a thousand in the -- in the federal courts before they get to trial. So, the first bellwether trial in the federal courts, Umer, would now be in November instead of April.

So, we'll keep you up to date, and thanks for your question.

Operator

Our next question comes from the line of Olivia Brayer with Cantor Fitzgerald. Your line is now open.

Olivia Brayer -- Cantor Fitzgerald -- Analyst

Hey, good afternoon. Thank you for the question. What were some of the dynamics that happened with Yescarta this quarter? And how should we be thinking about growth for 2024 from your cell therapy franchise just in light of the sequentially down quarter in 4Q? Thanks.

Cindy Perettie -- Executive Vice President, Kite

Thanks a lot, Olivia, for the question. This is Cindy. So, you know, we continue to be the -- the leaders in cell therapy. And I think the piece that Johanna mentioned is that we are looking at how do we expand beyond the existing ATCs.

So, the dynamics that we observed this quarter were capacity constraints within the existing ATCs that we have. We saw a little bit of in-class and out-of-class competition. And in parallel, we have been continuing to work on expanding our ATCs. So, today, we have over 400 ATCs globally.

We are moving out of urban centers and those academic centers into the community to meet patients where they are. As Andy suggested that bringing up those ATCs in the community is going to be really important part of our future strategy, but it does take a little bit longer than bringing an academic center up. So, we expect to be flat to slightly up in Quarter 1, and you'll start to see that return to growth in the second half of the year.

Operator

Our next question comes from the line of Geoff Meacham with Bank of America. Your line is now open.

Geoff Meacham -- Bank of America Merrill Lynch -- Analyst

Great. Thank you. Yeah, I have another one on cell therapy but more on the profitability. This is a, you know, a franchise that's almost 2 billion in sales.

You guys have, you know, improved the turnaround time, you reached scale, you treated a ton of patients. You know, what can you -- what can you tell us about the progress that you've made to making this, you know, a profitable franchise? I'm just thinking not -- not for the current products but also looking out, you know, five years-plus. Thank you.

Andy Dickinson -- Chief Financial Officer

Hey, Geoff, this is Andy. Thanks for the question. It's a great question. You're absolutely right, the cell therapy business has made tremendous progress over the last five or six years and evidenced most recently by the -- the faster turnaround time in manufacturing that we talked about in our prepared remarks, going from 16 days to 14 days. And again, it's just the beginning, from our perspective, of what we can continue to do at this business.

So, while we don't provide specific guidance, we've -- we have said when we -- when we announced the transaction that we expected to be profitable -- breakeven to profitable and accretive by -- by the end of year four. We got there shortly after that. All of the metrics that we look at on the business have improved over time. We've continued to make significant progress on our manufacturing efficiency and manufacturing costs despite the fact that we've opened three global manufacturing centers. And each time you do that, when you move to commercial manufacturing, it impacts your -- your gross margins, so I'm really proud of what the team has done.

And same thing on the operating costs, you see in the -- in the fourth quarter, we announced some restructuring charges, Geoff, that hit our GAAP -- our GAAP results. Part of that was a restructuring at Kite. And Cindy and her team looked at -- at the structure and made changes to the structure that we think will continue to drive growth and efficiency in the business over the long run. So, maybe the last thing I'd say is that when we look at the business, this is a business that we have line of sight to biologics margins and profitability. We're really growing the business, Geoff, as you know, for long-term sustainability and growth and less near-term profitability.

But it's certainly exciting that -- that the business is doing as well as it is.

Cindy Perettie -- Executive Vice President, Kite

I think the only thing I would add to Andy's comment is beyond the three manufacturing facilities, we also have our own viral vector facilities. So, given the fact that viral vector has had some supply challenges, that's something that we are not suffering from. So, we own the sort of end-to-end cost of goods for our products.

Jacquie Ross -- Vice President, Investor Relations

May we have our next question, please, Victoria?

Operator

Of course. Our next question comes from the line of Michael Yee with Jefferies. Your line is now open.

Mike Yee -- Jefferies -- Analyst

Hey, guys. Thank you for the question. We had an HIV question. There were some comments around the dynamics of the channel mix as it relates to HIV press -- pricing. And I was wondering if you could just remind us about what the driver of the benefit was in '22 and '23, and how that changed as we go into '24, and why that's difficult comps. Is that a change in mix between commercial and Medicaid swapping? Or maybe just explain that that would help us understand what's going on there for '24.

Thank you.

Johanna Mercier -- Chief Commercial Officer

Sure, Michael. Hi, it's Johanna. Let me take that one. So -- so, what you're referring to is actually we saw some pricing favorability in Q4 of '22 and the first half of 2023.

That pricing favorability was mainly driven by, actually, just the inflation being so high, and therefore, you know, some of our rebates are actually based on that inflation rate. And so, therefore, there was actually upside during those quarters. We knew that that was not going to repeat itself. So, we had kind of shared with you, I think from Q3 on, that this was going to normalize. And so, that was kind of what happened in the -- the -- the first half of 2023.

As we think about the second half of 2023, and namely the fourth quarter, what we did see there is very strong demand, and that continued throughout the whole year. But we had some fluctuations, some quarterly variabilities, mainly due to channel mix, and more government channels resulting in lower average realized price because of higher rebates. And so, you really have to look at it on a full-year basis. And so, that's why it's so important to know that HIV performance will always have some quarterly variabilities, and we always need to look at the full year to really get the full picture of what's going on. HIV for the full year of 2023 grew 6% with nearly $1 billion in revenue growth, driven by Biktarvy, obviously growing at 14% and at 48% share with 3% share growth in that year, outpacing all competitors.

And so, we're really proud of the demand-driven results that we've seen in 2023. And as we think about 2024 and our predictions for '24, we believe that you know, our expectations is going to be in line with HIV treatment, which is still about 2 to 3 points, layer on top of that the demand growth from Biktarvy and Descovy for PrEP, and that's why we're expecting about a 4% growth in HIV. So, that gives you the full picture of what's going on and what happened in the past. So, we don't expect that on a yearly basis, but on a quarterly basis, we do expect that variability.

And I would expect that that will continue as we move forward.

Operator

Our next question comes from the line of Chris Schott with J.P. Morgan. Your line is now open.

Chris Schott -- J.P. Morgan -- Analyst

Great. Thanks so much for the question. Can you just talk about the TIGIT program and what drove the decision to step up your investments here? And maybe as part of that, can you elaborate a little bit more on the decision to de-emphasize the PD-L1 high population, I guess, in favor of the -- the all-comer study? So, any -- any color, that would be appreciated. Thank you.

Andy Dickinson -- Chief Financial Officer

Hey, Chris, it's Andy. Maybe I'll start on the TIGIT program and the -- the revised agreement with Arcus that we announced last week, and Merdad can answer the second part of your question. You know, it's relatively simple. If you step back, we -- you've heard us say this before, but I'd reiterate that we value the partnership that we have with Arcus and the programs that their team has developed.

And the recent updates, to your question, to the partnership really allowed both companies to more efficiently deploy our teams and capital. We also focused on streamlining decision-making, and the additional capital allows us to expand the overall clinical study footprint. So, there are a number of things that both companies accomplish through the -- through the amendment. It does reinforce our support and belief in their programs broadly, not just TIGIT. But there's a lot to be excited about there that you'll -- you'll see play out over the coming years.

Merdad Parsey -- Chief Medical Officer

And -- excuse me, this is Merdad. I think you're referring to the ARC-10 study. And as you may recall, we started that study together with Arcus back in 2021 outside the U.S. with with the chemo comparator arm.

And at the time, there was really limited access to PD-1/PD-L1 inhibitors outside the U.S. And so, we subsequently updated that study March of last year to include PD-L1 inhibitors as standard of care was evolving. It took us time to get this all going. And while that was happening, we had a number of competitors launched similar trial in the space with their TIGIT antibodies. So, as a result of all that, the enrollment for the ARC-10 trial wasn't as robust as we had hoped for and as it had been.

And STAR-121, which is the all-comer study, was recruiting very well. And so, we decided to really prioritize our efforts for that all-comers population where we think we could be first or second in class. And it was really a prioritization to ensure that we could stay ahead and keep moving the molecule forward as quickly as possible.

Operator

Our next question comes from the line of Brian Abrahams with RBC Capital Markets. Your line is now open.

Brian Abrahams -- RBC Capital Markets -- Analyst

Hi, good afternoon. Thanks so much for taking my question. I realize this is pending KOL and regulatory discussions, but I was wondering if you could frame the potential next steps for the PD-L1 poor responders. Do you think this is a viable population for Trodelvy in second line longer? Might you also consider running another study in that population? And along those lines, I'm curious what you're expecting to see from the updated EVOKE-02 data this year and how that might shape your overall plans for Trodelvy in lung? Thanks.

Merdad Parsey -- Chief Medical Officer

Sure. This is Merdad again, Brian. So, maybe I'll take the second part first. On EVOKE-02, as you can imagine, we showed last year the ORR data.

And those data will continue to mature as time goes by, so we should start to see more PFS data this year that, you know, will demonstrate, we hope continued confidence in the front-line setting for Trodelvy based on that study that's running in parallel with EVOKE-03. So, we've gotten a lot of confidence for EVOKE-02 to support 03, and we are kind of keep updating that to make sure we get that. And it does actually reflect that from an earlier question around changes to EVOKE-03. And EVOKE-02 really keeps us in the right population, gathering data so that we make sure that there are no changes that are unnecessary.

In terms of the PD-1 non-responders in EVOKE-01, yeah, we -- I think we need more time to study the data, and we need to talk to the KOLs and the regulators to see there's -- I wouldn't rule out the possibility that we could discuss with regulators the possibility of using these data. And I want to be realistic and say that a second trial, another trial may be necessary. And that's something that we would -- we are thinking about right now, and we'll let you know as we update our situation there. And of course, we'll share the data from EVOKE-01 so that we can talk about it in more detail over time.

Operator

Our final question comes from the line of Colin Bristow with UBS. Your line is now open.

Colin Bristow -- UBS -- Analyst

Afternoon. Thanks for squeezing me in. Can you hear me?

Operator

Yes, we can hear you. Please go ahead.

Colin Bristow -- UBS -- Analyst

Maybe to ask Brian's question -- maybe on the back of Brian's question with regards to the observation that the OS benefit is greater than those non-responsive to prior I/O in the EVOKE-01 study, this seems to align with a recent study, which showed that TROP2 expression levels are associated with the primary resistance to checkpoint in the inhibition in non-small cell patients. And so -- and from that, obviously, there is a question on the potential synergy of TROP2 and -- and PD1s. I wondered if you have any thoughts on this or do you have any data which kid of give you comfort. Thanks.

Merdad Parsey -- Chief Medical Officer

We've spoken about this before. It's definitely something that we are cognizant of and following. One of the data readouts that we are continuing to collect right now from EVOKE-01 is TROP2 expression, and I think that will help us as we look at those data and share them to formulating hypotheses that may warrant change. So, that TROP2 expression is definitely something that we are focused on and will continue to follow and evaluate.

Operator

Thank you. I would now like to pass the conference back to Daniel for any closing remarks.

Dan O'Day -- Chairman and Chief Executive Officer

Well, thanks, everyone, for joining. We very much appreciate it. Before we conclude the call, let me just wrap up with a couple of comments and summary from what the team has accomplished over the past year and our setup for '24. First, our full-year performance reinforces the continued growth and strength of the business.

Gilead's HIV portfolio is unmatched with the standard of care daily oral treatment and our rapidly advancing pipeline with potentially best-in-class long-acting regimen. And in oncology, we now have a business that is annualizing at over $3 billion with clear opportunity for future growth. So, it's a base business last year this year. And second, our strong business allows us to take bold bets in innovation, and you'll see multiple updates on how those are playing out in 2024 and beyond.

We are pursuing science with a high potential impact for patients, and it comes with risks. But importantly, we built a resilient business and a robust portfolio that allows for that. In 2024, we expect at least 20 key updates across our HIV and oncology portfolios. And finally, I just want to thank the Gilead teams for all the hard work and delivering our strong full-year performance and advancing our portfolio.

We look forward to keeping all of you updated on our progress throughout 2024. Thanks again for joining today.

Operator

[Operator signoff]

Duration: 0 minutes

Call participants:

Jacquie Ross -- Vice President, Investor Relations

Dan O'Day -- Chairman and Chief Executive Officer

Johanna Mercier -- Chief Commercial Officer

Merdad Parsey -- Chief Medical Officer

Andy Dickinson -- Chief Financial Officer

Tyler Van Buren -- TD Cowen -- Analyst

Dan ODay -- Chairman and Chief Executive Officer

Salveen Richter -- Goldman Sachs -- Analyst

Leon Wang -- Barclays -- Analyst

Cindy Perettie -- Executive Vice President, Kite

Terence Flynn -- Morgan Stanley -- Analyst

Umer Raffat -- Evercore ISI -- Analyst

Olivia Brayer -- Cantor Fitzgerald -- Analyst

Geoff Meacham -- Bank of America Merrill Lynch -- Analyst

Mike Yee -- Jefferies -- Analyst

Chris Schott -- J.P. Morgan -- Analyst

Brian Abrahams -- RBC Capital Markets -- Analyst

Colin Bristow -- UBS -- Analyst

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