Pfizer's CD3-bispecific Phase 2 trial in MM shows ORR of 60%June 5, 2022 – Pfizer Inc. (NYSE: PFE) today announced new data from a planned interim analysis of the Phase 2 MagnetisMM-3 registration-enabling trial of elranatamab in people with relapsed/refractory multiple myeloma (RRMM) whose disease is refractory to at least one agent in each of three major classes of medications approved for the disease.
Elranatamab is an investigational B-cell maturation antigen (BCMA) CD3-targeted bispecific antibody in development for the treatment of multiple myeloma (MM). MagnetisMM-3 is an open-label, multicenter, single arm, Phase 2 study evaluating the safety and efficacy of elranatamab monotherapy in patients with RRMM.
https://www.pfizer.com/news/press-release/press-release-detail/pfizer-presents-first-data-planned-interim-analysis-pivotal
This notwithstanding, while T-cell-engaging CD3-bispecific antibodies (CD3-bsAbs) are promising modalities for cancer immunotherapy, with this therapy reaching clinical practice for hematological malignancies, the absence of sufficient infiltrating T cells is a major barrier for this bispecfic's therapy efficacy in solid tumors.
In 2020, Groeneveldt et al. demonstrated that oncolytic reovirus can be effectively emplyed as an effective strategy to enhance the efficacy of CD3-bsAbs in immune-silent solid tumors.
The researchers showed that ONCY's pelareorep is able to precondition the tumor microenvironment thus converting CD3-bispecific treatment into effective immunotherapy.
The researchers concluded that oncolytic reovirus administration represents an effective strategy to induce a local interferon response and strong T-cell influx, thereby sensitizing the tumor microenvironment for subsequent CD3-bsAb therapy and that this bispecifc combination therapy warrants further investigation in patients with non-inflamed solid tumors.
https://jitc.bmj.com/content/8/2/e001191