Preliminary safety and response data from 52 subjects with different solid tumors who received monotherapy (INT230-6 alone), and 7 subjects that received INT230-6 combined pembrolizumab, have been generated and reported for ASCO in 2020. Thirteen (13) highly refractory patients have had disease stabilization for more than 6 months. INT230-6 is dosed per volume tumor. A minimum threshold of dose per volume needed to saturate tumors as seen in nonclinical models appears to be relevant in humans. Analysis of dose response relationship is ongoing. Many subjects’ tumors increase over baseline, then regress on subsequent scans (potential pseudo progression). Several patients showed some size reduction of one or more non injected lesions in lymph nodes, liver, lung, perineum, and retroperitoneal areas (abscopal effects to visceral lesions). Safety has been good with most adverse events being of low grade (1 or 2). There were no grade 4 or higher events, 2 drug related SAE’s (pain), and no events that limited dosing.
Phase 2 studies including 4 studies of INT230-6 combined with pembrolizumab, which is being supplied by Merck, to treat pancreatic, MSI-stable colon, bile duct and squamous cell cancer are planned. In addition, 3 studies combining INT230-6 with ipilimumab, which is being supplied by Bristol Myers Squibb are also planned.
Our products show potent anticancer effectiveness in challenging mouse tumor types. Animals having a complete response become immunized against the cancer. Using mouse models of severe, late-stage pancreatic, breast, melanoma and colon cancers, our unique formulations (especially lead product INT230-6) given intratumorally (IT) were more effective with less observed toxicity than intravenous (IV) and IT dosing of the same drugs.
In early studies INT230-6 completely regressed large tumors in animals treated. INT230-6 was able to clear completely mouse Colon26 tumors greater than 300 mm³. In one study INT230-6 increased median overall survival of animals from 16 days with no treatment to 77 days using one 5-day cycle at a dose scalable to human tumors. Median survival using the product was also superior to the best drugs given systemically; 42 days vs. 77 days at comparable dose. Mechanism studies showed that INT230-6 induces a strong CD8+ and CD4+ mediated adaptive immune response. Ninety percent (90%) of the animals having the complete response became fully protected following subcutaneous or intravenous re-inoculation of the same cancer—a response that lasted the entire life of the animal. INT230-6 also inhibited the growth of murine breast cancer and reduced the formation of breast cancer metastases. Dual tumor modes showed injection in a primary tumor could regress distal, untreated lesions.
Our engineers developed validated assays and established GMP controlled manufacturing of INT230-6. Clinical batches produced under GMP and tested in mice showed significantly greater efficacy than research lab produced formulations. Using the GMP batches up to 80% of animals dosed achieved a complete response with every injected tumor regressing from baseline.Back to Technology