Novavax established itself as the leader in the race to market a vaccine for respiratory syncytial virus (RSV) with positive results from a phase II efficacy trial in older patients.
The finding that the RSV F vaccine reduced the incidence of an infection that causes hundreds of thousands of hospitalisations a year should make the project a strong candidate for partnering. Validation of the finding – whether use of the vaccine in pregnant women will confer protection for their babies – will be closely watched when a second phase II trial reads out in coming weeks.
Big market, few options
Novavax shares rose 30% to $14.50 in early trading today on the news announced post-market yesterday. With a big pharma competitor in the form of GlaxoSmithKline’s GSK3003891A not expected to wrap up phase II trials until the end of 2015 – and then only with immunogenicity data available – Novavax’s advantage is clear.
The trial in 1,600 adults aged 60 and over showed a statistically significant reduction in incidence of symptomatic RSV disease of 44%, and RSV disease with symptoms of lower respiratory tract infection of 46%, versus placebo.
RSV is a common respiratory disease, as nearly every person is infected with it before the age of two. However, severe cases put a burden on the healthcare system, with the US Centers for Disease Control and Prevention reporting 177,000 hospitalisations and 14,000 deaths among adults 65 and older, in addition to 58,000 hospitalisations and 2.1 million outpatient visits among children under five.
This profile should make RSV F a strong candidate for a preventive vaccine, especially as existing interventions have been disappointing. Valeant’s Virazole, an inhaled ribavirin, has limited data supporting it in symptomatic disease and requires extensive equipment monitoring and maintenance when used with patients on ventilators; experts believe it has little effect on the course of disease (Therapeutic Focus - Hopes on the horizon for respiratory syncytial virus, August 7, 2012).
On the preventive side, Astra’s antibody Synagis has been on the US market since 1998, but because of its $8,000-a-year cost and five-dose treatment course it is used only in high-risk paediatric patients.
On to phase III
Novavax said it is preparing to advance into phase III at the end of the year. With $315m in cash at June 30 in marketable securities it probably has sufficient funding to see the trial through to its conclusion; it believes that 8,000 patients or more could be necessary. This makes Novavax not necessarily in any hurry to deal, but it looks like an option with both regulatory and commercial advantages for any big pharma partner or buyer.
The vaccine has an FDA fast-track designation and, if maternal and paediatric data are as promising as the trial that reported yesterday, it has the potential to be used in a broad population. On the other hand vaccines tend to be a lower-margin business, so only companies with an established trade might be interested in Novavax’s offering; the top vaccines company, Glaxo, already has its own candidate, but Sanofi or Pfizer might be interested.
It is also worth noting that Pfizer’s pneumococcal vaccine Prevnar 13 is forecast to become the sixth-biggest selling drug in the world in 2020, so it is not as if there is little commercial potential for a respiratory disease vaccine.
No doubt this potential will become clearer as more data emerge.