GSK plc stock (GB0009252882): asthma drug setback meets solid pipeline momentum

Respiratory specialist GSK faces a regulatory setback for its once-daily asthma drug in the US, even as new respiratory syncytial virus and HIV products support growth. What this tension between pipeline risk and commercial execution means for GSK plc stock.

GSK plc stock is back in focus after US regulators issued a complete response letter for the company’s once-daily asthma treatment, raising questions about a key pipeline asset while newer vaccines and HIV therapies continue to drive revenue growth, according to a company update published in May 2026 and recent product disclosures from GSK’s investor materials.

In mid-May 2026, GSK reported that the US Food and Drug Administration had issued a complete response letter (CRL) for the new drug application for depemokimab, its long-acting biologic candidate for eosinophilic asthma, and the company stated that it plans to work with the agency to address outstanding questions without providing a detailed timeline for a resubmission, according to statements in its regulatory news updates and investor communications during May 2026.

As of: 27.05.2026

By the editorial team – specialized in equity coverage.

At a glance

• Name: GSK
• Sector/industry: Pharmaceuticals and vaccines
• Headquarters/country: United Kingdom
• Core markets: Global prescription drugs and vaccines, including significant exposure to the US market
• Key revenue drivers: Vaccines, HIV therapies, specialty respiratory medicines
• Home exchange/listing venue: London Stock Exchange (ticker: GSK)
• Trading currency: GBP in London; ADRs also trade in USD in the United States

GSK plc: core business model

GSK positions itself as a focused biopharmaceutical company that concentrates on the discovery, development and commercialization of prescription medicines and vaccines, with particular emphasis on infectious diseases, HIV, respiratory conditions and immunology, according to descriptions in its corporate overview and annual reporting.

The company’s strategy in recent years has revolved around reallocating capital towards higher-growth specialty and vaccine franchises and away from lower-margin, non-core consumer health operations, a shift that was underscored by the separation of its former consumer health business into a standalone company in 2022, as explained in GSK’s 2022 and 2023 annual reports.

GSK emphasizes a research model that seeks to combine genetic and functional genomics, human challenge trials and artificial intelligence–supported discovery tools to increase the probability of technical success in its pipeline, and management has repeatedly highlighted this approach in its research and development presentations and capital markets day materials.

Within this framework, the respiratory and immunology portfolio remains central, with asthma and chronic obstructive pulmonary disease medicines such as Trelegy and Nucala contributing significant revenue alongside the company’s vaccines unit, which has been a major growth driver following the launch of the respiratory syncytial virus (RSV) vaccine Arexvy, according to recent quarterly updates and product sales discussions.

Main revenue and product drivers for GSK plc

In recent financial periods, GSK has highlighted three pillars of revenue growth: vaccines, HIV medicines and specialty medicines, with vaccines including shingles and RSV products showing strong momentum based on sales data disclosed in earnings releases for 2023 and the first quarter of 2024.

The company’s shingles vaccine Shingrix has remained one of its largest products by sales, particularly in the United States and Europe, where demand in older adults has supported double-digit revenue growth in some recent quarters, according to figures reported in GSK’s 2023 annual report and subsequent quarterly updates published in early 2024.

Another key driver is Arexvy, GSK’s RSV vaccine for older adults, which launched in 2023 and quickly became a meaningful contributor to the vaccines portfolio, with management indicating robust uptake in the United States and an expanding presence in other markets in a series of earnings calls and press statements from late 2023 and early 2024.

The HIV business operates largely through ViiV Healthcare, in which GSK holds a majority stake, and features therapies such as dolutegravir-based regimens and long-acting injectable options that address treatment-experienced and treatment-naïve patients; GSK has reported resilient performance in this franchise despite gradual competitive pressures from alternative therapies, according to its recent quarterly disclosures.

Specialty medicines, including respiratory drugs like Trelegy and biologic therapies such as Nucala, add another layer of diversification, and the company has described this segment as an important contributor to margin improvement given the higher pricing and more targeted patient populations compared with some older primary-care respiratory products.

Against this backdrop of multiple commercial pillars, the pipeline setback for depemokimab is notable because it targets a patient group with high unmet need in severe eosinophilic asthma, and management had previously presented this candidate as a potential future growth driver in immunology, based on pipeline presentations and R&D day materials released before the FDA’s complete response letter in May 2026.

Industry trends and competitive position

GSK operates in a global pharmaceutical sector that is experiencing rising demand for vaccines, oncology and specialty immunology treatments, alongside intense pricing scrutiny in major markets such as the United States and Europe, trends that are regularly highlighted in sector analysis by large investment banks and industry groups.

In vaccines, GSK competes with companies such as Pfizer, Moderna, Sanofi and others, but maintains strong positions in areas such as shingles and now RSV for older adults, with analysts and industry observers noting that the company moved relatively early in several subsegments and has built extensive manufacturing and distribution capabilities to support global launches.

Within HIV, competition from other large biopharmaceutical groups has intensified as patent expiries approach for older therapies, yet long-acting injectable regimens and combinations remain a differentiating factor for ViiV Healthcare, and GSK’s disclosures suggest that the company sees continued opportunity to defend market share and potentially expand into prevention and treatment-prevention overlaps.

In respiratory and immunology, rivals such as AstraZeneca and Amgen are investing heavily in biologics for asthma and related indications, and the regulatory setback for depemokimab could affect how investors weigh GSK’s long-term position in this niche, although the company continues to market established products and develop additional pipeline candidates in related diseases.

Overall, GSK’s competitive profile reflects a trade-off between solid, cash-generating franchises in vaccines and HIV and the scientific, regulatory and commercial uncertainty that accompanies a large late-stage pipeline, particularly in immunology and specialty respiratory indications, a balance that many large pharmaceutical peers are also navigating.

Why GSK plc matters for US investors

For US investors, GSK offers exposure to global demand for vaccines and specialty medicines through both its primary listing in London and American depositary receipts that trade in US dollars, and the company frequently cites the United States as one of its largest single markets in annual and quarterly reports.

The performance of products like Shingrix and Arexvy is closely linked to US health-care utilization patterns and vaccination campaigns for older adults, meaning that changes in US reimbursement policies, Centers for Disease Control and Prevention recommendations and private payer behavior can directly influence GSK’s revenue trajectory and margin profile.

HIV therapies marketed through ViiV Healthcare are also heavily exposed to the US market, where treatment guidelines, generic competition and the pace of adoption of long-acting regimens play important roles, and GSK has discussed these dynamics on multiple investor calls when explaining its medium-term growth framework and capital allocation priorities.

From a portfolio-construction standpoint, some US investors look at large European pharmaceutical groups like GSK as a way to diversify currency and regulatory risk while still tapping into US health-care spending trends, although such diversification also introduces foreign-exchange and policy risk that can affect reported earnings and dividend capacity.

Conclusion

GSK plc stands at an interesting juncture, with strong commercial momentum in vaccines and HIV medicines set against a notable regulatory setback for its depemokimab asthma program in the United States, and investors are likely to monitor how quickly the company can address the FDA’s questions and whether additional data will be needed. The breadth of the existing portfolio, including Shingrix, Arexvy and established HIV regimens, provides a buffer while management works through pipeline challenges and continues to invest in late-stage assets across infectious diseases and immunology. For US-focused portfolios, GSK offers a diversified way to participate in global health-care demand with meaningful US market exposure, but the stock’s medium-term trajectory will depend heavily on execution in bringing new medicines through the regulatory process and sustaining competitive positions in crowded therapeutic areas.

Disclaimer: This article does not constitute investment advice. Stocks are volatile financial instruments.