Kolltan Pharmaceuticals, a privately held biopharmaceutical company, has  treated its first cancer patient with Kolltan’s lead drug candidate, KTN3379, as part of a phase I clinical study evaluating safety, preliminary evidence of antitumour activity, and pharmacokinetics. KTN3379 is a human monoclonal antibody that blocks the activity of ErbB3, a member of the ErbB family of receptor tyrosine kinases.

KTN3379 has a dual mechanism of action that blocks activity of ErbB3 when activated by stimulatory growth factor neuregulin or by other receptor tyrosine kinases (such as ErbB2) in the absence of neuregulin. Currently marketed products, both antibodies and small molecules, that are active against other members of the ErbB family have shown clinical benefit in the treatment of a range of solid tumours, including lung, head and neck, colorectal and breast malignancies. However, there is currently no marketed drug that binds to and inhibits the action of ErbB3.

Dr Jerry McMahon, president and CEO of Kolltan, commented, "The ErbB3 receptor tyrosine kinase plays a key role in many cancers by driving growth, survival and resistance of tumors. KTN3379 is a novel human antibody that potently blocks ErbB3 signaling by binding to a unique epitope on the extracellular domain of the kinase to disable this target especially when it is recruited by the ErbB2 (HER2) and EGF receptors." He added, "KTN3379 has the potential of being combined with other targeted therapies where KTN3379 would block ErbB3 in a way that would overcome limitations by current marketed agents targeting other ErbB targets in cancer patients."

Dr Carolyn Sidor, senior vice president and chief medical officer at Kolltan, said, "This important phase I study is focused on generating the safety, antitumour activity and pharmacokinetic data needed to progress this novel drug candidate into clinical studies for several tumor types that may be dependent on ErbB activity. We are excited that Karmanos has treated the first patient in our clinical study and look forward to advancing quickly through these initial stages of clinical testing."

Kolltan is advancing a new generation of therapeutics in oncology and other diseases by creating novel biologic agents that can modulate the function of receptor tyrosine kinases (RTKs).