Immunocore Holdings plc has presented at the Conference on Retroviruses and Opportunistic Infection (CROI) the first safety and activity data with IMC-M113V, a bispecific soluble TCR therapy built on the company's ImmTAX® technology which is being developed for the treatment of people living with HIV (PLWH). Initial Phase 1 trial data: In the single ascending dose part of the trial, three dose levels of IMC-M113V, given as a single IV infusion, were evaluated: a starting dose of 1.6 mcg, based on the minimum anticipated biological effect level (n=1), 5 mcg (n=1) and 15 mcg (n=10). All doses were well tolerated.

There were no serious adverse events, significant changes in hematology or chemistry, nor cytokine release syndrome or neurotoxicity. Plasma viral load remained suppressed throughout dosing and follow-up. In addition, transient, dose-dependent increases in serum IL6 occurred 8-24 hours post-infusion.

Five out of the ten participants who received the 15-mcg dose showed a >4-fold rise in IL6, which had been prespecified as indicative of pharmacodynamic activity based on prior experience from clinical trials with KIMMTRAK (tebentafusp), the company's first ImmTAX therapy now approved for the treatment of metastatic or unresectable uveal melanoma. Enrollment underwayin next part of the trial: The company has started enrolling people living with HIV in the multiple ascending dose (MAD) part of the trial, to identify a safe and tolerable dosing schedule that could lead to reduction in the viral reservoir and control of HIV after stopping antiretroviral therapies (ART), or functional cure. The MAD trial will enroll up to 28 participants.