A small Seattle biotech wants to take on GlaxoSmithKline's emerging Shingrix blockbuster. RA Capital is on board
GlaxoSmithKline’s Shingrix has quickly become one of the company’s best-selling products since first winning FDA approval in 2017. But a new biotech believes it can do better — and RA Capital is listening.
Curevo Vaccine, a Seattle-based company, debuted a $60 million Series A on Thursday led by the prominent life sciences VC, aiming to fund a Phase IIb study for its shingles vaccine candidate. The program, known as CRV-101, will be measured against Shingrix as the control and pits the two shots head-to-head.
CEO George Simeon told Endpoints News he believes Curevo’s shot can provide similar efficacy levels to Shingrix while tamping down on the side effects. That will be a tough task as Shingrix proved 97% effective in preventing shingles for healthy adults aged 50 to 69, and 91% effective in all such adults older than 50.
Researchers were encouraged by the biotech’s Phase I study, Simeon added, prompting the push into the nearly 700-patient Phase IIb trial that started enrolling last month.
“We’re going to be looking at immune responses” in the Phase II study, Simeon said. “Of course, if there are shingles cases, we will look, but that requires a much larger trial to look for actual clinical endpoints. So now we’ll be looking at immunologic endpoints, looking at how the two vaccines compare from a humoral and cell mediated immune response perspective.”
The reason Curevo is so confident lies in the adjuvants the vaccines are using. Shingrix’s adjuvant contains a compound called QS-21 in which two main issues arise, Simeon said. First, the emerging consensus points to this compound as the primary driver of Shingrix adverse events — the shot causes a strong immune response and symptoms can last for two to three days before usually resolving on their own.
And second, QS-21 is in high demand because it can only be made from certain trees native to Chile, Peru and Bolivia. The Covid-19 pandemic continuing to snarl the global supply chain is hardly helping things, Simeon said.
Curevo’s adjuvant, meanwhile, is tailored to fit into the TLR4 receptor in an effort to utilize the immune pathway and lessen the shot’s side effects. It also goes after the same antigen used in chickenpox vaccines, Simeon said, saving Curevo the trouble of trying to validate a completely new target.
This combination, Simeon believes, will give the biotech a shingles vaccine both non-inferior to Shingrix and causes less side effects.
“What we’re looking to show is that we elicit the same immune responses,” he said. “We’d like to show that we’re non inferior in terms of efficacy, but that we have a better tolerability profile than Shingrix.”
Topline Phase IIb data are expected at the beginning of next year, and if Curevo likes what it sees, it plans to undertake a pivotal Phase III study comparing CRV-101 to Shingrix again in a much larger setting.
Shingrix has legitimized GlaxoSmithKline’s vaccine franchise, netting more than $1 billion in sales in 2018, its first full year on the market. The shot pulled in nearly $2.8 billion for the company in 2020 and won a new approval last year for use in all immunocompromised adults, but the pandemic significantly dented sales growth as figures fell to $2.33 billion last year.
Curevo will have a long road ahead to compete with something like that, with or without Covid-19 disruptions. Even so, it’s taking an untraditional route to finance its vaccine, having already run its Phase I study before any major venture round and recruiting RA Capital — which generally invests in crossovers — for the hefty Series A.
The shot itself comes out of a nonprofit research institute and biopharma from South Korea known as MOGAM and GC Pharma, respectively. GC Pharma licensed the vaccine and funded Curevo through Phase I, though the biotech has been running all of the preclinical and clinical studies.
“This is why we have a little bit of an atypical Series A,” Simeon said. “I guess it would be more typical to see this type of fundraise and this stage of company as a Series B or C, but because they provided that initial financial support, we were able to get to the end of our Phase I results.”
In addition to RA, other investors included Adjuvant Capital, which has ties to the Bill and Melinda Gates Foundation, as well as Janus Henderson Investors and EN Investment. GC Pharma also chipped in again.