IMMUNOMEDICS' ImmuRAID-MN3 IMAGING AGENT FOR INFECTIOUS DISEASES WILL ENTER PHASE III; AGENT TARGETS RADIOLABELED GRANULOCYTE MAb FRAGMENTS

Immunomedics' ImmuRAID-MN3 will enter Phase III studies during calendar 1992, company officials reported at a Dec. 2 presentation to the New York Society of Security Analysts. ImmuRAID-MN3 is the company's first product outside the cancer area. The imaging agent uses the company's proprietary radioimmunotherapy technology to label granulocyte-targeting monoclonal antibody fragments with technetium-99. The MAb attaches to the concentrations of granulocytes resulting from infection, and an infected site is located by identifying concentrations of the technetium. Immunomedics VP-Medical Affairs Carl Pinsky said the company has had Phase I/II studies under way at New York's Mt. Sinai medical center using ImmuRAID-MN3 for detecting infected hip prostheses. In addition to infected prostheses, possible uses of the imaging agent are fever of unknown origin -- which Pinksy noted could be important for septic shock and AIDS -- and earlier detection of osteomyelitis and other bone infections. Immunomedics filed a product license application for its lead product -- ImmuRAID-CEA -- for colon cancer detection in April 1991. Estimating a two-year PLA review by FDA, Immunomedics' 1992 objectives include initiating the construction of a commercial production facility. ImmuRAID-CEA is a MAb-based agent for in vivo detection of carcinoembryonic antigen (CEA)-producing tumors, such as colon cancer. The agent employs Immunomedic's proprietary technetium radio-immunodetection (RAID) technology. Company President and Chief Operating Officer Russell McLauchlan reported that "renovation of our Newark, N.J. [pilot production] facility began in October; this site is expected to provide for initial demand" of ImmuRAID-CEA. Site selection is under way for a commercial- scale manufacturing facility, he noted. Immunomedics is anticipating FDA approval for two uses of ImmuRAID-CEA, Pinsky said -- confirmation of cancer recurrence or metastasis in complement with computed tomography (CT) or magnetic resonance imaging and detection of occult cancer in patients with a history of colon cancer when there are signs that cancer is recurring but remains undetected by other imaging techniques. Such signs might include rising levels of CEA in the blood. Pinsky told the analysts that ImmuRAID-CEA has advantages over other radiolabeled-monoclonal antibodies in that it uses both a MAb fragment and technetium rather than other radioisotopes such as indium. The Immunomedics' technology uses a single-arm, or Fab, fragment. Other imaging products in development by Immunomedics are ImmuRAID-CEA for breast and lung cancer and ImmuRAID-LL2 for B- cell lymphoma. Both are scheduled to move into Phase III in 1992. The company is also developing ImmuRAID-AFP for liver and germ cell tumors that are alpha-fetoprotein producing. The instant imaging kit is currently in Phase I/II and has an orphan product designation. On the therapeutic side, Immunomedics is planning to begin Phase I trials with ImmuRAIT-Rhenium for treating colorectal cancer and has begun Phase I/II trials of ImmuRAIT-CEA for colorectal cancer and ImmuRAIT-LL2 for B-cell lymphoma. Immunomedics' funding comes in part from a July 1991 licensing deal with Adria Labs that gives Adria the U.S. and Canadian marketing rights to Immunomedics' cancer-imaging products ("The Pink Sheet" July 15, T&G-13). Immunomedics also is looking in Europe for marketing partners and is in negotiations for corporate partners in Korea, Israel, South America and Australia/New Zealand.