GSK Posts Stellar Results from Phase 3 RSV Vaccine Trial

In competition with some of pharma’s biggest heavyweights, GSK posted positive Phase 3 trial results for its respiratory syncytial virus (RSV) vaccine. Based on the results, GSK plans to submit the vaccine, GSK3844766A, for regulatory approval by the end of the year, racing with Pfizer, AstraZeneca, Sanofi, Janssen, and Moderna, all of which have candidates in Phase 3 trials. 

Racing for the World’s First RSV Vaccine

RSV is a common respiratory virus, most prevalent in infants and older adults. Immunocompromised individuals face the highest risk associated with the disease because it can lead to bronchitis or pneumonia. It can also exacerbate existing conditions like chronic obstructive pulmonary disease (COPD) and asthma. The disease causes nearly 30,000 deaths in adults across industrialized nations each year. 

GSK’s RSV vaccine targets the two prominent strains leading to serious disease and death in adults, RSV A and B. According to a press release from the company, the vaccine demonstrated equally positive results for both strains. 

The Phase 3 trial, AReSVi-006, enrolled over 26,000 adults over 60 to evaluate the safety and efficacy of the vaccine. In patients with at least two severe lower respiratory signs, the vaccine proved 94.6% effective. Data from patients with pre-existing comorbidities demonstrated an efficacy rate of 94.6%. In a cohort of older patients between 70 and 79, the vaccine demonstrated a 93.8% efficacy rate. Across the entire participant population, the vaccine had an overall efficacy of 82.6%.

Tony Wood, Chief Scientific Officer at GSK, said, “These are truly exceptional results given that today RSV remains one of the major infectious diseases without a vaccine, despite over 60 years of research.”

Along with the promising results, the vaccine demonstrated a tolerable safety profile with the most adverse events consisting of injection site pain, fatigue, myalgia, and headache. GSK said it would continue assessments and annual revaccination schedules of the trial’s participants to analyze the vaccine’s long-term safety and efficacy. 

Based on the most recent results, GSK said it plans to submit the vaccine for regulatory approval in the second half of this year. Depending on its competitors’ regulatory progress, GSK’s vaccine could be the first RSV vaccine ever to make it to market.

Related Article: AstraZeneca, Sanofi’s RSV Antibody Recommended For Approval In EU

Sizing up the Competition

Even with impressive data, GSK is not at the finish line yet. The pharma giant still has to undergo regulatory approval, which may entail proving its vaccine is just as or even more effective than its competitor’s. 

Last month the Committee for Medicinal Products for Human Use (CHMP) recommended AstraZeneca’s and Sanofi’s jointly developed RSV vaccine, Beyfortus, for EU approval. Though it is for the same virus as GSK’s vaccine, Beyfortus is designed for use in infants. 

In August, Pfizer announced Phase 3 trial results from its bivalent vaccine. The company said it proved 85% effective in older adults. Like GSK’s vaccine, Pfizer’s candidate, RSVpreF, targets RSV A and B strains. Pfizer also plans to submit its vaccine for regulatory approval soon. 

Moderna and Janssen each have RSV vaccines in Phase 3 trials. Neither company has results Phase 3 results yet, but Janssen initiated a Phase 3 study in September last year, and Moderna started its Phase 3 portion in February this year.

With decades of development, the pharmaceutical industry is closer than ever to releasing a safe and effective RSV vaccine. GSK is neck and neck with some of the industry’s strongest competitors, and its most recent Phase 3 trial results will bolster its upcoming regulatory submission. 2023 will surely see the world’s first commercial RSV vaccine, but only time will tell which company will gain the coveted opening approval. 

Author

Reed Slater