WALTHAM, Mass., Oct 11, 2010 (BUSINESS WIRE) -- ImmunoGen, Inc. (Nasdaq: IMGN), a biopharmaceutical company that develops targeted anticancer therapeutics using its Targeted Antibody Payload (TAP) technology, today announced the presentation of encouraging clinical data for the Company's lorvotuzumab mertansine (IMGN901) targeted anticancer compound at the 35th European Society for Medical Oncology (ESMO) Conference being held in Milan, Italy, October 8-12, 2010.
Lorvotuzumab mertansine is designed to target and kill cancer cells that express CD56, a protein. This targeted anticancer compound is a potential treatment for Merkel cell carcinoma (MCC), small-cell lung cancer (SCLC), ovarian cancer, multiple myeloma, and other CD56+ tumors. It is wholly owned by ImmunoGen.
Clinical Data Reported
The data reported today are from an early-stage clinical trial evaluating lorvotuzumab mertansine in CD56+ solid tumors. During the dose-escalation phase of the trial, patients with any type of CD56+ solid tumor were eligible for enrollment. In the ongoing expansion phase of the trial, enrollment is limited to patients with MCC, SCLC, or ovarian cancer.
A total of 64 patients with CD56+ solid tumors had been enrolled at the time of data cut-off for presentation. Among these, 45 patients could be quantitatively assessed for changes in overall tumor burden. Thirteen (29%) of these 45 patients had a reduction in tumor volume ranging from 1.3 - 100%, and another 10 patients (22%) had no discernable increase in tumor burden.
Findings in Merkel Cell Carcinoma
Patients with Merkel cell carcinoma are being enrolled in the expansion phase of this trial as promising activity has been reported with lorvotuzumab mertansine for MCC, and the Company is assessing whether to initiate a pivotal trial with the compound for this use.
Metastatic MCC is a rare and aggressive neuroendocrine cancer of the skin. Among patients diagnosed with metastatic MCC, median survival is less than seven months. There are no approved therapies for metastatic MCC, and typically the disease progresses rapidly (within 1 to 2 months) on the therapies currently used.
Thirteen patients with metastatic MCC had been enrolled in the study at the time of data cut off. Five (38%) of these patients had notable clinical benefit:
1 patient had a complete response (CR) and has remained disease free for more than 5 years;
1 patient had a partial response (PR) that evolved to a CR, and has been disease free for at least 17 months; and
3 patients had clinically relevant stable disease for this patient population, remaining on lorvotuzumab mertansine for at least three months.
Findings in Small-Cell Lung Cancer
Twenty-six patients were enrolled with SCLC, which has commonalities with MCC in biological characteristics, clinical course and response to treatments. SCLC tumors generally respond to first-line treatment but then recur. Survival at that stage is usually less than 6 months.1
While all of the SCLC patients enrolled in this trial had cancer that had recurred following treatment with other therapies, three patients had clinically meaningful stable disease and another patient with refractory disease achieved an unconfirmed PR.
ImmunoGen plans to begin a study later this year to assess lorvotuzumab mertansine for first-line treatment of SCLC used in combination with standard care.
"These findings are encouraging in light of the prior treatments these patients have received and the stage of their disease at the time of study entry," commented James O'Leary, MD, Vice President and Chief Medical Officer. "We believe it's important to assess lorvotuzumab mertansine as part of a combination regimen, as cancer is typically treated with several agents with different mechanisms of action. The combination trial planned in SCLC and the one underway in multiple myeloma are expected to be particularly significant to determining the potential opportunity for this compound."
About the Clinical Trial Reported
The patients enrolled at the time of data cut-off for presentation consisted of 26 patients with SCLC, 16 with neuroendocrine tumors, 13 with MCC, and 9 patients with other types of CD56+ solid tumors. The first ovarian patient entered the study after that time.
In the expansion phase of the trial, lorvotuzumab mertansine is being administered at a dose of 60 mg/m²/day for three consecutive days every 21 days.
About Lorvotuzumab Mertansine
Lorvotuzumab mertansine, a TAP compound, consists of a CD56-binding antibody with ImmunoGen's potent cancer-cell killing agent, DM1, attached to it using one of the Company's engineered linkers.
Lorvotuzumab mertansine has been granted orphan drug designation for MCC in the US and Europe. It also has been granted orphan drug status for SCLC in the US and is in the process of receiving this designation in Europe.
About MCC, SCLC and Ovarian Cancer
MCC is an aggressive neuroendocrine cancer of the skin that typically occurs on the head/neck, most often in individuals of European ancestry. There are approximately 1,900 new cases of MCC diagnosed in the US each year, with the incidence considered to be increasing.2 An estimated 28,000 new cases of SCLC are expected to be diagnosed in the US in 2010, and 22,000 new cases of ovarian cancer.3, 4 Based on published literature and Company research, CD56 is expressed on virtually all cases of MCC and SCLC and on approximately 58% of ovarian cancer tumors.
About ImmunoGen, Inc.
ImmunoGen, Inc. develops targeted anticancer therapeutics using the Company's expertise in tumor biology, monoclonal antibodies and potent cancer-cell killing agents. The Company's TAP technology uses monoclonal antibodies to deliver one of ImmunoGen's proprietary cancer-cell killing agents specifically to tumor cells. There are currently seven TAP compounds in the clinic, with a wealth of clinical data reported with the technology. ImmunoGen collaborative partners include Amgen, Bayer Schering Pharma, Biogen Idec, Biotest, Genentech (a member of the Roche Group), Novartis, and sanofi-aventis. The most advanced compound using ImmunoGen's TAP technology, T-DM1, is in Phase III testing through the Company's collaboration with Genentech. More information about ImmunoGen can be found at www.immunogen.com.