Recently, Regeneron said it had the capacity to make tens of thousands of doses of its two-antibody cocktail REGN-COV2 a month for use in the treatment of COVID-19. If the capacity is used to make prophylactic doses of REGN-COV2, Regeneron could make hundreds of thousands of vials a month.
Now, Regeneron and Roche have outlined plans to significantly increase its manufacturing capacity. Working together, the companies expect to increase capacity “by at least three and a half times” and retain the ability to bring still more capacity online if needed.
The vagueness of Regeneron’s earlier comments about capacity make it impossible to say precisely how many doses of REGN-COV2 it expects to ship in partnership with Roche. However, it is plausible that Regeneron and Roche will have capacity to ship more than 1 million prophylactic doses a month, or more than 100,000 therapeutic doses.
To hit the targeted 3.5 times increase in output, Regeneron and Roche have agreed to dedicate some manufacturing capacity to REGN-COV2 each year. Regeneron has begun the process of transferring the technology needed to manufacture the antibody cocktail to Roche.
Once the transfer is complete, Roche will start gearing up to distribute REGN-COV2 outside of the US. Regeneron will handle distribution in the US. Each company will pay its own distribution costs in its designated territories and split the cost of ongoing phase 1 and 3 clinical trials.
The involvement of Roche could help Regeneron meet demand even if it needs to use large doses of REGN-COV2 to prevent and treat COVID-19. In a preclinical study, Regeneron gave rhesus macaques 50 mg/kg prophylactic doses of its antibody cocktail.
That dose, which reflects the use of 25 mg/kg per antibody, is higher than the amount of antibody typically used in therapeutics. Merck’s Keytruda is administered at 2 mg/kg, while even Johnson & Johnson’s Darzalex, a drug known to use a relatively large amount of antibody, is given at 16 mg/kg.
A preclinical study run around the time of the 2003 SARS crisis found a 10 mg/kg dose of an antibody protected ferrets against the coronavirus at the center of that outbreak. Regeneron is yet to say what doses it is testing in its clinical trials of REGN-COV2, which now include a phase 3 study to assess the ability of the antibody cocktail to prevent COVID-19 in people who live with infected individuals.