Outstanding questions overshadow GSK’s respiratory syncytial virus win
The soon-to-be pure-play pharma company GSK desperately needed a hit in respiratory syncytial virus – the vaccine for older adults is considered its most valuable pipeline project. Relief all round then at news of success for the phase 3 Aresvi 006 trial, though lack of detail makes the extent of the win unknowable. GSK described the result as “statistically significant and clinically meaningful”, adding that the effect size was consistent across secondary endpoints and in those aged 70 and above. The company has previously described efficacy above 50% as clinically meaningful, 70% very good and above 80% outstanding; analysts want to see at least 70%, believing that anything less would leave GSK susceptible to projects coming behind. Durability of response is another consideration, with some analysts concerned that regulators might want to see data over more than one RSV season. GSK is confident that its vaccine, which uses the same adjuvant as Shingrix, will provide long-term protection; this is an issue that all contenders must address, of course, and could be an important differentiator in the long term. With Pfizer and J&J also expecting pivotal readouts later this year, the race to market will soon be on.
|Late-stage pipeline of adult RSV vaccines
|Protein subunit vaccine, adjuvanted
|Ph3 Aresvi 006 in adults ≥60 toplined positive June 2022
|Protein subunit vaccine
|Ph3 Renoir trial in adults ≥60, data due H2 2022
|Adenovirus type 26 viral vector vaccine
|Ph3 Evergreen trial in adults ≥60, data due H2 2022
|Recombinant antigen vaccine
|Ph3 trial in adults ≥60, data due H2 2023
|mRNA vaccine encoding RSV glycoprotein F
|Ph3 portion of ph2/3 ConquerRSV trial in adults ≥60 began Feb 2022
|Source: Evaluate Pharma.