The shares of the biotech company Arcturus Therapeutics Holdings Inc. they were down 55% on Tuesday as investors responded to the results of a phase 1/2 trial of their COVID-19 vaccine candidate that one analyst said was disappointing.
Arcturus ARCT based in San Diego,
He said on Monday afternoon that he had received approval from the Singapore Health Sciences Authority to move forward with a phase 2 study of his vaccine candidate ARCT-021 which will enroll up to 600 volunteers.
Approval is based on phase 1/2 trial data that showed that the vaccine produced neutralizing antibodies after a dose, albeit at lower levels than rival candidates. Arcturus hopes its vaccine does not require a booster injection, which makes administration easier than vaccines that require two doses.
The company’s goal is to generate provisional Phase 2 data in early 2021 that will determine the optimal dosage and initiate a global Phase 3 study during the second quarter of 2021.
Raymond James downgraded Arcturus shares to outperform the news market and said the data was “disappointing.”
“Although the latter data set does not completely affect single-shot ARCT-021, which may provide protection against COVID-19 infection in phase 3, the lack of neutralizing antibody (NAb) titers of SARS-CoV-2 at or higher levels observed in convalescence will reduce our confidence that ARCT-021 will be able to achieve competitive levels of vaccine efficacy with a single dose, “wrote analysts led by Stephen Seedhouse in a notes to customers. “At a minimum, the question will be asked by the market and will not be answered until phase 3, thus limiting the short-term rise and justifying a Market Performance rating.”
Neutralizing antibody titers reached the lower end of the range of convalescent plasma titers seen with vaccines developed by Pfizer Inc. PFE,
with the German partner BioNTech SE BNTX,
and for Moderna Inc. MRNA,
He said. These vaccines have received emergency use authorization from the U.S. Food and Drug Administration and are currently being deployed throughout the United States and other countries.
These vaccines have shown effects of 90%, while that of Arcturus is potentially as low as 62%, Seedhouse said.
“We admit that reaching 60% VE north with a single dose would be a decent result for the saRNA mechanism and would make the ARCT-021 a viable vaccine (at least as competitive as AZD1222) given the high global demand,” he said. write. “But this level of NAb titles … doesn’t support the more optimistic outlook we had previously about ARCT-021 … it’s not competitive with Pfizer / Modern and … it won’t make ARCT-021 a preferred vaccine in the US ”
Shares of Arcturus have gained 280% in 2020, while the SPF S&P Biotech ETF XBI,
has gained 50% and the S&P 500 SPX,
has risen 16%.