Biotech Values

[hirogen]

OCRX stated that their internal models predict STOP-HE (after patient upsizing) will show a 1.5-2-day improvement relative to SoC in the primary endpoint, which is more bullish than my own prior assessment of an improvement of about 1 day

I listened to the 1Q earnings call and the company's presentation, which gave more details than I expected. They confirmed that the increase in trial size restores power to original design 80%. I believe I understand their trial power and sizing methodology (see slide 8 from webcast). With the upsizing of the trial, I think the control arm is performing better than the original assumption. Using the company's method, my initial estimate for the IA is relative symptom improvement of ~35% at worst (vs ~50% by trial design) which would make ~1 day improvement still a possibility.

Looking at different trials with a Lactulose regimen, the response rates are quite varied. HE appears to be a very heterogenous disease. Given how they sized the trial, I am wondering if they are censoring patients that improve after the 5 day primary treatment regimen as that may have an effect on preserving power.