April 21, 2015
By Alex Keown, BioSpace.com Breaking News Staff
NEW YORK – Pfizer Inc. ‘s late-stage trial drug inotuzumab ozogamicin for the treatment of acute lymphoblastic leukemia, met its first endpoint in a Phase III study.
Pfizer said the drug demonstrated a higher complete hematologic remission rate in adult patients compared to results achieved with standard chemotherapy. The 326-patient study will continue the Phase III trial for the second end point, survival rates.
Mace Rothenberg, Pfizer’s chief medical officer, said relapsed and refractory acute lymphoblastic leukemia is a particularly difficult disease to treat in adults. Meeting of the first endpoint of the Phase III trial shows the drug has the potential to be an important new treatment option for patients with relapsed or refractory disease, he said in a statement.
Acute lymphocytic leukemia, which impacts bone marrow, is the most common type of cancer in children, and treatments result in a good chance for a cure. However, the chance of a cure in adults with ALL is greatly reduced, according to the Mayo Clinic. Approximately 20 to 40 percent of newly diagnosed adults with ALL are cured with current treatment regimens, including chemotherapy. For patients with relapsed or refractory adult ALL, the five-year overall survival rate is less than 10 percent. Drugs used to treat ALL include Novartis’s Gleevec (imatinib), Tasigna (nilotinib) and Bristol-Myers Squibb’s Sprycel (dasatinib). These drugs are approved only for people with the Philadelphia chromosome-positive form of ALL.
Pfizer is making plans to discuss the results of the trial with the U.S. Food and Drug Administration.
Inotuzumab ozogamicin is an investigational antibody-drug conjugate comprised of a monoclonal antibody targeting CD22,7 a cell surface antigen expressed on approximately 90 percent of B-cell malignancies, eight linked to a cytotoxic agent. When inotuzumab ozogamicin binds to the CD22 antigen on malignant B-cells, it is internalized into the cell, where the cytotoxic agent calicheamicin is released to destroy the cell, according to a company statement.
Inotuzumab ozogamicin originates from a collaboration between Pfizer and Celltech, now UCB. Pfizer has sole responsibility for all manufacturing and clinical development activities for this molecule.Pfizer’s stock is slightly up this morning, with a high of $35.40 per share.
Pfizer is set to report first-quarter earnings results on April 28. Investors will be looking for revenue stabilization in the wake of patent losses, cost reductions to temper a drop in sales, and positive commentary regarding the company’s pipeline, according to analysts at investopedia.com.
In December, Pfizer entered into a partnership with Opko Health for that company’s human growth hormone for the treatment of pediatric and adult growth hormone deficiency. The treatment is currently in clinical trials.