05-18-2020, 08:17 AM
Moderna reported its phase I results (via press release):
https://investors.modernatx.com/news-rel...na-vaccine
As best I can tell, they haven't been published yet, but the press release is fairly promising:
The fact that they saw neutralizing antibodies at levels comparable to convalescent plasma is a good sign. On the other hand, the safety is a bit worrisome:
Grade 3 adverse events are "severe", so to see some in a small study like this is concerning. You don't want to see grade 3 systemic symptoms in a vaccine study unless it is a very rare side effect, so to see multiple cases when only 15 patients have been enrolled in the cohort is a red flag. Fortunately, that's only in the highest dose level, and only after the second dose, and neutralizing antibodies were seen at the lowest dose level.
They are going forward with 50 µg and 100 µg in the phase 2 trial, which makes sense. I am worried that they will see systemic symptoms at these doses. I anticipate it will be less frequent than with the 250 µg dose level, but again, the safety threshold for a vaccine trial has to be pretty high. An early vaccine for COVID-19 might see a relaxed safety criteria compared to something like influenza or MMR, but it will still have to be fairly safe as it will be given to millions of otherwise healthy people.
I look forward to seeing the paper when it is published.
BC
https://investors.modernatx.com/news-rel...na-vaccine
As best I can tell, they haven't been published yet, but the press release is fairly promising:
Quote:At day 43, two weeks following the second dose, at the 25 µg dose level (n=15), levels of binding antibodies were at the levels seen in convalescent sera (blood samples from people who have recovered from COVID-19) tested in the same assay. At day 43, at the 100 µg dose level (n=10), levels of binding antibodies significantly exceeded the levels seen in convalescent sera.
The fact that they saw neutralizing antibodies at levels comparable to convalescent plasma is a good sign. On the other hand, the safety is a bit worrisome:
Quote:The sole incidence of a grade 3 adverse event in the 25 µg and 100 µg dose cohorts was a single participant at 100 µg who experienced grade 3 erythema (redness) around the injection site. To date, the most notable adverse events were seen at the 250 µg dose level, comprising three participants with grade 3 systemic symptoms, only following the second dose. All adverse events have been transient and self-resolving. No grade 4 adverse events or serious adverse events have been reported.
Grade 3 adverse events are "severe", so to see some in a small study like this is concerning. You don't want to see grade 3 systemic symptoms in a vaccine study unless it is a very rare side effect, so to see multiple cases when only 15 patients have been enrolled in the cohort is a red flag. Fortunately, that's only in the highest dose level, and only after the second dose, and neutralizing antibodies were seen at the lowest dose level.
They are going forward with 50 µg and 100 µg in the phase 2 trial, which makes sense. I am worried that they will see systemic symptoms at these doses. I anticipate it will be less frequent than with the 250 µg dose level, but again, the safety threshold for a vaccine trial has to be pretty high. An early vaccine for COVID-19 might see a relaxed safety criteria compared to something like influenza or MMR, but it will still have to be fairly safe as it will be given to millions of otherwise healthy people.
I look forward to seeing the paper when it is published.
BC

