Gilead Sciences (NASDAQ:GILD) executives on Tuesday outlined the company’s rationale for three recently announced transactions—its proposed acquisitions of Tubulis, Ouro Medicines, and Arcellx—framing the deals as additive to an already active late-stage pipeline and consistent with the company’s business development discipline.
Management says pipeline momentum remains the priority
Chairman and CEO Daniel O’Day said the company views the group of transactions as strengthening Gilead’s portfolio across its three therapeutic areas of focus: virology, oncology, and inflammation. O’Day said that even before the deals, 2026 was “already an exciting moment” for the company, citing expectations for five Phase 3 updates across those areas and “up to 10 ongoing and potential new launches through 2027.” He also emphasized that Gilead does not expect major losses of exclusivity “until 2036.”
Tubulis: ADC platform and lead ovarian cancer program
Chief Medical Officer Dietmar Berger said Gilead reached an agreement to acquire privately held clinical-stage Tubulis, which he described as having “an industry-leading platform” for antibody-drug conjugates (ADCs). Berger noted Gilead’s existing ADC franchise anchored by Trodelvy and said Gilead had partnered with Tubulis in 2024 on a Gilead-owned ADC that remains in preclinical development.
Berger detailed Tubulis’ proprietary conjugation chemistries—P5 and Alco5—and its “Tubutecan” platform, which combines P5 conjugation with an exatecan payload. He said the platform enables “consistent and high drug-to-antibody ratio” and stability in circulation, which he argued helps unlock targets “that have been elusive with prior ADC attempts,” including NaPi2b.
Berger highlighted Tubulis’ investigational lead asset, TUB-040, in ovarian cancer. He said NaPi2b is expressed in “approximately 90% of ovarian cancer cells” with minimal expression in normal cells. At ESMO in October 2025, Phase 1 data in 46 patients with platinum-resistant ovarian cancer showed a confirmed overall response rate of 50% (or 59% including unconfirmed responses), with responses that “occurred early and deepened over time,” Berger said. He added that more than 130 patients have now been treated, though he said the company was not yet sharing additional details.
On safety, Berger said the Phase 1 data showed “potentially lower rates of Grade 3 plus” adverse events and “no discontinuations due to adverse events,” adding that there were no clinically relevant bleeding, pneumonitis, ocular toxicity, stomatitis, or neuropathy observed. He said TUB-040 is already in the Phase 2 portion of its study in platinum-resistant ovarian cancer and is expected to enter registrational Phase 3 studies in 2027.
In Q&A, CFO Andrew Dickinson said the upfront valuation for Tubulis was “supported by the ovarian cancer indications alone,” while also pointing to platform value and other assets. Berger attributed previous NaPi2b challenges to therapeutic index and said TUB-040’s stability in circulation could reduce unwanted systemic toxicity.
Ouro Medicines: BCMAxCD3 T-cell engager for autoimmune disease
Berger also discussed Gilead’s definitive agreement to acquire privately held Ouro Medicines, describing its portfolio as focused on T-cell engagers for autoimmune conditions. He said the transaction includes a partnership with Galapagos, with shared investment and development.
Ouro’s lead asset, OM-336 (gamgertamig), is a BCMA x CD3 bispecific T-cell engager. Berger said it has “potentially superior potency and lower CRS” than other BCMA T-cell engagers, is administered subcutaneously, and has shown proof of concept in “approximately 60 patients” across immune-mediated diseases. He listed multiple orphan autoimmune indications in development, including autoimmune hemolytic anemia, immune thrombocytopenia, pemphigus vulgaris, pemphigus foliaceus, and idiopathic inflammatory myopathies, with potential Phase 3 registrational trials “as early as 2027.”
Berger said OM-336 could potentially extend into more than 20 immune-mediated diseases driven by pathogenic B and plasma cells, naming myasthenia gravis, rheumatoid arthritis, Sjögren’s disease, and systemic lupus erythematosus as examples. He also positioned OM-336 as complementary to anito-cel, a BCMA-directed CAR T, suggesting the combination of approaches could support a shift toward “potentially durable immune reset.”
Arcellx: consolidating anito-cel and expanding cell therapy platforms
Kite EVP Cindy Perettie said the Arcellx acquisition follows more than three years of collaboration on anito-cel, calling it “transformative and potentially best-in-disease” BCMA cell therapy. Perettie said Gilead is “less than nine months away” from an FDA PDUFA date in fourth line-plus multiple myeloma and is preparing for a potential launch, while also advancing a pivotal trial in second line-plus and preparing for newly diagnosed settings.
Perettie cited ASH data from iMMagine-1 in fourth line-plus multiple myeloma showing “deep, and durable efficacy” and a differentiated safety profile, including “no delayed or non-ICANS neurotoxicities and enterocolitis.” O’Day said the “tipping point” for full acquisition included de-risking from data seen at the end of last year and acceptance of the FDA BLA, and he emphasized speed of execution and platform value, including Arcellx’s D-Domain binders.
Perettie said full ownership would streamline commercialization with a single field-facing team and could reduce confusion that can arise when two companies market together. She also said bringing development fully in-house would enable faster decision-making to explore additional opportunities such as smoldering multiple myeloma and community studies.
Financial framework: limited 2026 opex impact; debt plans outlined
Dickinson said all three transactions are expected to close in the second quarter and that the company will update full-year 2026 guidance “in due course.” Excluding transaction-related IPR&D, he said Gilead does not expect a “significant increase in operating expenses in 2026.” He added that R&D should rise modestly versus the company’s start-of-year guidance, with R&D as a percentage of total revenue expected to be “less than 20%” for the full year.
On Arcellx, Dickinson reiterated prior expectations that the deal would be “modestly dilutive to non-GAAP EPS in 2026 and 2027, and accretive thereafter.” He said Gilead plans to fund the Arcellx and Ouro acquisitions with cash and a short-term $5 billion loan expected to be repaid before the end of 2026. For Tubulis, Dickinson said Gilead expects to issue senior unsecured notes in the second quarter of 2026, with total long-term debt expected to be about $24 billion, “flat” with the level at the end of 2025.
Gilead said it plans to report first-quarter 2026 results on May 7.
About Gilead Sciences (NASDAQ:GILD)
Gilead Sciences, Inc, founded in 1987 and headquartered in Foster City, California, is a biopharmaceutical company focused on the discovery, development and commercialization of medicines in areas of high unmet medical need. The company initially built its reputation in antiviral therapies and has since expanded into oncology, cell therapy and inflammatory diseases. Gilead operates a global research and commercial organization, conducting clinical development and selling medicines in markets around the world.
Gilead’s product portfolio is anchored by antiviral therapies for HIV and viral hepatitis.
