Advancing innovative cell and gene therapies with the potential to transform cancer therapy
At ASCO 2023, we are presenting promising data on two of our clinical programs, and each supports the potential of our cutting-edge approaches to cell and gene therapy in the treatment of cancer. We are particularly enthusiastic about this data because both investigational therapies were evaluated in solid tumor indications, which typically have not responded as well to some immunotherapy approaches, particularly CAR-T therapies.
Abstract #5590: Phase 1/1b study of PRGN-3005 autologous UltraCAR-T cells manufactured overnight for infusion next day to advanced stage platinum resistant ovarian cancer patients
Abstract 5590 reports data from the ongoing Phase 1/1b study of PRGN 3005 in patients with advanced stage, platinum resistant ovarian cancer. PRGN-3005 is an investigational UltraCAR-T® therapy. Conventional CAR-T manufacturing methods require weeks of growing engineered T cells in culture in order to generate sufficient amounts to achieve a therapeutic effect, during which time patients’ health may continue to decline. In contrast, our transformative UltraCAR-T platform allows T cell engineering to be performed overnight, allowing patients to begin treatment the day after their cells are collected. The UltraCAR-T point-of-care manufacturing process eliminates time- and reagent-intensive processes that are barriers to CAR-T therapy.
Data presented at ASCO show that 20% of the 25 evaluable patients had a response in at least one target lesion. In the seven patients who received intravenous (IV) PRGN-3005 following lymphodepletion (LD) the disease control rate (DCR) was 85.7% at first restaging, with a decreased target tumor burden in 4/7 (57%), and a 27.4% average decrease in CA125. One patient had a 28% decrease in target tumor burden after receiving a second infusion of PRGN-3005 after 12 months. No deaths, dose-limiting toxicities, neurotoxicity, grade ≥3 Cytokine Release Syndrome (CRS), or unexpected on-target/off-target toxicities related to PRGN-3005 reported.
View PRGN-3005 abstract
Abstract #2628: Phase I evaluation of PRGN-2009 alone and in combination with bintrafusp alfa in patients (pts) with recurrent/metastatic (R/M) HPV-associated cancers (HPV-C)
Abstract 2628 reports data from the ongoing Phase 1 study of PRGN-2009 alone and in combination with bintrafusp alfa in patients with recurrent/metastatic HPV-associated cancers. PRGN-2009 uses our proprietary AdenoVerse™ and UltraVector® platforms to deliver optimized HPV antigens that stimulate the immune system to attack HPV-associated tumors. Precigen uses gorilla adenovirus for its vector, which allows for repeat administration given that humans have little to no prior immunity to this virus. This is an important difference compared with other adenovector-based IO approaches that use adenoviral strains that are common in humans.
Data presented at ASCO show that 4/6 patients who received PRGN-2009 monotherapy in the dose-escalation portion (DEP) of the study achieved stable disease, with the longest duration being 14.9 months. Of the 10 evaluable patients who received PRGN-2009 in combination with BA in the combination portion (CP), one patient, who was resistant to previous treatment with a checkpoint inhibitor, achieved a complete response and two patients (one of whom was resistant to checkpoint inhibitor therapy) achieved partial responses. The overall response rate was 30.0% and the median overall survival was 7.4 months for DEP and 12.5 months for CP. Post vaccination 14/16 (88%) patients developed T-cell responses to HPV-16 and/or HPV-18 (6/6 in DEP and 8/10 in CP). There were no > Grade 3 treatment-related adverse events attributable to PRGN-2009.
View PRGN-2009 abstract
We are especially excited about the positive results for PRGN-3005 in patients with ovarian cancer, as solid tumors have typically not responded as well as hematologic cancers to traditional CAR-T therapy. We also believe the activity of PRGN-2009 observed in patients who previously failed checkpoint inhibitor therapy is also very promising, as they suggest that PRGN in combination with BA may provide a new treatment option for this subset of difficult-to-treat patients.