NEW YORK – Epsilogen on Tuesday said it began a Phase Ib trial of its investigational therapeutic antibody MOv18 IgE in patients with FRα-expressing, platinum-resistant ovarian cancer.
In the trial, researchers will assess MOv18 IgE in about 45 patients whose disease has progressed after no more than four lines of prior therapy. To be eligible for the trial, patients' tumor tissue must test positive for FRα expression using the Leica Biosystems BN3.2 antibody and have immunohistochemistry scores of 1+, 2+, or 3+ representing antigen expression in least 5 percent of tumor cells.
In part one of the trial, investigators will evaluate the safety and tolerability of MOv18 IgE and determine the maximum tolerated dose and a recommended expansion dose. In part two, the researchers will track the drug's anti-tumor activity and disease progression in patients receiving the recommended expansion dose of MOv18.
MOv18 IgE targets FRα, an antigen found on more than 70 percent of ovarian cancers. It was developed by King's College London in collaboration with Cancer Research UK. The antibody is constructed of a portion of the stem region of an IgG antibody appended to an intact IgE, combining the functions of both antibodies. IgE has a highly potent immune effector function evolved to provide immunity to parasites and recruits immune cells by different mechanisms. Epsilogen expects it will have a longer tissue half-life and greater potency at lower doses compared with conventional IgG antibodies.
In a Phase I dose-escalation trial conducted by Cancer Research UK, MOv18 IgE was well tolerated with few serious adverse events and showed preliminary evidence of anti-tumor activity.