Sonnet BioTherapeutics announces FDA acceptance of IND for SB221 trial

Sonnet BioTherapeutics announced that the IND for SB221, the Phase 1b/2a clinical trial of SON-1010 in combination with Roche’s anti-PD-L1 checkpoint inhibitor, atezolizumab, has been accepted, and the study can begin in the US for the treatment of PROC. The trial consists of a modified 3+3 dose-escalation design in Part 1 to establish the maximum tolerated dose of SON-1010 with a fixed dose of atezolizumab. Clinical benefit in PROC will be confirmed in an expansion group to establish the recommended Phase 2 dose. Part 2 of the study will then investigate SON-1010 monotherapy, its use in combination with atezolizumab, or the standard of care for PROC in a randomized comparison to show proof-of-concept. SON-1010 is a proprietary version of recombinant human Interleukin 12, configured using the FHAB technology that targets tumor and lymphatic tissue, that provides a mechanism for dose sparing due to its extended pharmacokinetic properties. The extension of PK observed with the FHAB technology may improve the safety and efficacy profile of IL-12, which may be complemented further with a variety of potent immuno modulators linked to the molecule in a bispecific construct. Atezolizumab is an immune checkpoint inhibitor approved for the treatment of some of the most aggressive and difficult-to-treat forms of cancer. The characteristics of ovarian cancer present a unique opportunity to assess the combination of these two agents in an indication that persists as a large unmet medical need.