Biotech Values

[dewophile]

VACC - Hep B

https://investors.vaccitech.co.uk/news-and-events/news-releases/news-release-details/vaccitech-announces-positive-topline-final-data

HBV002 was an open-label study to evaluate the safety, tolerability and immunogenicity of VTP-300, with or without low-dose nivolumab, in people with chronic HBV who are virally suppressed with oral anti-viral therapies. In the HBV002 study, 55 participants were randomized into four groups to receive combinations of VTP-300 and low-dose nivolumab, with follow-up for nine months after the first dose.

In the VTP-300 monotherapy group (Group 2; N=18), five patients had baseline HBsAg under 100 IU/mL. Of those five patients, three showed meaningful and durable reductions of HBsAg of 0.9-1.4 log10 at five and eight months after the last dose of VTP-300.

Group 3 (N=18) patients received VTP-300 in combination with a single low dose of nivolumab at the time of the booster dose. The mean log10 reduction in HBsAg was 0.8 at 3, 6, and 9 months (n=18, 18, and 17, respectively), with more prominent declines observed in patients with baseline HBsAg lower than 1,000 IU/mL (mean log10 reduction of 1.0 at 3, 6, and 9 months [n=13 at each timepoint]). Five patients in this group had baseline HBsAg lower than 100 IU/mL, of which three had persistent declines ranging from 1.4 to 3.4 log10 at 9 months. Moreover, two of these patients developed non-detectable HBsAg at 3 months, which persisted in both patients at eight months after the last dose, as assessed in a post-hoc analysis...
A Phase 2b clinical trial to evaluate timing of low dose nivolumab and additional doses of the MVA boost component of VTP-300 (HBV003; NCT05343481) has been initiated in multiple countries within the Asia-Pacific region, with interim data expected in Q4 2023. In addition, a Phase 2a clinical trial, in collaboration with Arbutus Biopharma Corporation (NASDAQ: ABUS), is evaluating the safety, antiviral activity and immunogenicity of VTP-300 administered after Arbutus’ AB-729 in 40 virologically-suppressed chronic HBV patients, with interim data expected in Q4 2023.

I'm surprised at how many patients here had surface Ag <100, 5/18 in the two groups highlighted. I would imagine that in the real world only 5% or so of patients w chronic hep B have that low of a level. In the Bepirovirsen 2b study 7 out of 138 patients on the high dose/duration arm had HBSAg levels <200 (all had undetectable levels at EOT, and 6/7 maintained this to 6 months post tx). (Figure S9 https://www.nejm.org/doi/full/10.1056/NEJMoa2210027). GSK's phase 3 is enrolling patients with surface Ag <3000, and has a predefined look at efficacy in those <1000.
I know several companies have therapeutic vaccines in the pipeline and this could be a component of combination therapy at some point but clearly too weak as a monotherapy to amount to anything