Fosun Pharma has stopped development of BioNTech’s first COVID-19 vaccine, following the lead of its German partner by picking BNT162b2 as the candidate to take to market.
BioNTech signed up to work with Fosun to bring a COVID-19 vaccine to China in March. The deal, which is worth up to $135 million, led to Fosun registering a phase 1 trial of mRNA vaccine BNT162b1 with the Chinese authorities in July. Less than one week later, BioNTech and its global partner Pfizer selected BNT162b2 as the candidate to take forward into phase 2/3.
Now, Fosun Chief Medical Officer Aimin Hui has told Reuters that BNT162b2 is also the preferred shot for the Chinese market. Fosun has opted against further development of BNT162b1, choosing instead to run a bridging study that may enable it to use global BNT162b2 data to support approval in China.
Chinese authorities have become more accepting of data generated overseas in recent years. If all goes to plan, the bridging study will enable Fosun to show the safety and efficacy seen in the global program is applicable to the Chinese population and win approval “around the same time” as the vaccine is authorized in other countries.
The switch to BNT162b2 could provide benefits. BioNTech and Pfizer selected the vaccine as their phase 2/3 candidate, despite it entering the clinic second, after linking it to a lower rate of adverse events than BNT162b1.
In a phase 1/2 trial, 17% of 18- to 55-year-olds who received 30 μg of BNT162b2 reported related adverse events. The comparable adverse event rate for BNT162b1 was 50%. BioNTech and Pfizer also linked BNT162b1 to a higher rate of adverse events in 65- to 85-year-olds. Fewer people who received BNT162b2 suffered systemic events, and those that did reported milder events.
The immune responses linked to the two vaccines were similar, leading BioNTech and Pfizer to pick the more tolerable candidate for late-phase development. Given the potential for the vaccine to be given to hundreds of millions of people as well as face intense scrutiny and, in some quarters, skepticism, tolerability could be an important enabler of successful mass immunization programs.
It remains unclear when those immunization programs will start. Last week, Pfizer said its trial was yet to see the 32 COVID-19 cases that will trigger the first look at the late-phase data.