• Preliminary tumor response data support initiation of Phase 2 studies in Head & Neck and BRAF mutant cancers
  • Two new clinical trials in Head & Neck and BRAF Thyroid cancers initiated and enrolling patients

NEW HAVEN, CT, USA I October 16, 2015 I Kolltan Pharmaceuticals, Inc. today announced interim tumor response data from an ongoing Phase 1b clinical trial in patients with solid tumors, as well as plans to expand the Phase 1b trial and the initiation of two new clinical trials of KTN3379, a human anti-ErbB3 (HER3) monoclonal antibody drug candidate being developed for the treatment of adult patients with various solid tumors. The results to date of the ongoing Phase 1b trial showed evidence of tumor shrinkage in patients treated with KTN3379 in combination with other targeted therapies, including the following:

  • A confirmed complete response in a patient with squamous cell carcinoma of the head and neck who previously progressed on cetuximab monotherapy; this patient has been treated with KTN3379 and cetuximab for six months and remains on study therapy;
  • Three additional patients with BRAF V600E mutations in either non-small cell lung or colorectal cancers have been treated with the combination of KTN3379 and vemurafenib for up to six months and continue on study;
    • The two BRAF mutant non-small cell lung cancer patients have demonstrated preliminary evidence of partial responses; one patient was previously treated with a different BRAF inhibitor and progressed on therapy; and
  • The tolerability of the combinations of cetuximab or vemurafenib with KTN3379 in this trial remains acceptable and supports the continuation of study therapy with these combinations. The side effect profile of the combination arms is consistent with expectations and includes diarrhea and skin rashes that were managed with medications and dose reductions.

“Targeting ErbB3 for the treatment of multiple types of cancers is an important strategy as ErbB3 participates in tumor survival pathways and may serve as a resistance mechanism for widely used therapies,” stated Gerald McMahon, Ph.D., President and Chief Executive Officer of Kolltan. “The results for this first-in-human study of KTN3379 demonstrate an acceptable safety profile for further clinical development of the drug candidate, and the sustained treatment of several late-stage cancer patients is encouraging. The new data, in addition to emerging data from our three ongoing clinical trials with KTN3379, are planned for presentation at upcoming medical conferences.”

“We are pleased to see the clinical progress of KTN3379 and early evidence of tumor shrinkage in two of our combination arms of the trial,” said Dr. Ronald Peck, Chief Medical Officer and Senior Vice President, Clinical Development at Kolltan. “We are planning multiple Phase 2 studies of KTN3379 based on its pharmacokinetics, mechanism of action, and, now, early evidence of efficacy in selected solid tumors, including squamous tumors of the head and neck and BRAF mutant tumors. Two new clinical studies in cancers of the head and neck and thyroid are now active and are planned to generate data shortly to complement the encouraging data to date in our Phase 1b combination study.”

The ongoing Phase 1b clinical trial is a multi-center, open-label, dose escalation study, in which KTN3379 was administered at doses of 5, 10, 15, or 20 mg/kg, or a fixed dose of 1200 mg, once every three weeks as one hour IV infusion. The expansion cohorts of the trial were designed with six to twelve patients each using 20 mg/kg of KTN3379 in combination with cetuximab, erlotinib, vemurafenib, or trastuzumab. An increase in the number of patients in the vemurafenib combination arm of the trial is planned.

In addition to the expansion of the ongoing Phase 1b clinical trial, Kolltan has initiated two new clinical studies with KTN3379 which are enrolling patients. The Phase 1b study in thyroid cancer will evaluate the treatment of patients with radioactive iodine refractory BRAF mutated cancers with a combination of KTN3379 and vemurafenib to determine if the combination can reverse the resistance to radioactive iodine. The study is being conducted at Memorial Sloan Kettering Cancer Center with Dr. Alan Ho as the Principal Investigator.

The new clinical study in head and neck cancers will evaluate tissue responses to KTN3379 in newly diagnosed patients who are treated with KTN3379 prior to their surgical resection. This study is expected to provide valuable information on the effects of KTN3379 on biomarkers of activity to design additional studies in this cancer. The study has been initiated at the University of Pittsburgh Medical Center with Dr. Seungwon Kim as the Principal Investigator and at the University of California at San Francisco with Dr. Jonathan George as the Principal Investigator.

About KTN3379

KTN3379 is a human monoclonal antibody designed to block the activity of ErbB3 (HER3), a receptor tyrosine kinase (RTK) that belongs to the epidermal growth factor receptor, or EGFR, family. ErbB3 is believed to be an important receptor regulating cancer cell growth and survival. ErbB3 is expressed in many cancers, including head and neck, breast, lung, gastric, and melanoma. While there are several successful currently marketed products targeting two members of the EGFR family, there are none that directly target ErbB3. In cancer, ErbB3 activation can be driven by its ligand, neuregulin (NRG), or in its absence, through overexpression of its co-receptor ErbB2 (HER2).

About Kolltan Pharmaceuticals

Kolltan, a privately held clinical-stage company, is focused on the discovery and development of novel, antibody-based drugs targeting RTKs for the treatment of cancer and other diseases with significant unmet need. Kolltan’s founders and members of its management team have deep expertise and a proven track record in drug discovery, development, and commercialization of innovative therapeutics, including drugs targeting RTKs. Kolltan is working in close collaboration with the laboratory of Kolltan Co-Founder, Dr. Joseph Schlessinger, as well as the Yale University medical and scientific community. The Company has a broad and novel portfolio of therapeutic biologics targeting multiple RTKs that are advancing in clinical and preclinical development and are expected to generate multiple near-term milestones. Kolltan’s most advanced product candidates include KTN3379, a human monoclonal antibody designed to block the activity of ErbB3 which is in Phase 1b clinical trials in solid tumors, and KTN0158, a humanized monoclonal antibody designed to block the activation of KIT, which is being developed as a potential therapy for cancer and mast cell-related diseases and is anticipated to enter clinical trials in early 2016.

SOURCE: Kolltan Pharmaceuticals