Replies to post #247759 on Biotech Values

[dewophile]

Of the 11 patients, how many were seropositive for HBsAg mAbs at the start of the off-treatment period?

10, so at least 4 patients who were both Ag negative and Ab positive relapsed.
Incidentally, in GSK's Bepirovirsen trial only half the patients who achieved sustained responses were SAb positive 6 months post treatment per the NEJM article (https://www.nejm.org/doi/full/10.1056/NEJMoa2210027

Of the participants who had a primary-outcome event, 7 (50%) receiving NA therapy and 6 (50%) not receiving NA therapy had anti-HBs at the end of the trial

), but it looks like these responses remain durable for the most part despite half not seroconverting:

https://events-distribution.easl.eu/from.storage?image=XuxJjSOSJud6SrESrXs_xXw-pMLvnbLBTlVmp4fL3kXjivbTWXsy9jPhDtNGZqOg0

7/9 (78%) of those who ceased NA had complete data with ≥3 months of follow-up, and 6/7 (86%) maintained
response 3 months post NA cessation. 4/9 (44%) had complete data with ≥6 months of follow-up
post NA cessation, of whom 100% (4/4) maintained response.

For Not-on-NA pts (n=12).. 9/12 responders (75%) had complete data with ≥3 months of follow-up and 78% (7/9) maintained response 3 months after enrolling into B-Sure. 3/12 (25%) had complete data with ≥9 months of follow-up, of whom 100% (3/3) maintained response 9 months into B-Sure.

So 3 of the 16 patients between the 2 arms (on NA and not on NA) for whom there is at least 3 months of data beyond the 6 month trial endpoint (so 9 months after stopping therapy) relapsed between month 6 and 9+ off therapy, but all 7 patients for whom there is data 6+ months past the trial endpoint (i.e. 12 months after stopping therapy) continue to remain undetectable. GSK is going to follow these patients for 3 years total