Staff Writer

With multiple trials advancing for its unpartnered cancer drug candidate lorvotuzumab, ImmunoGen Inc. is seeking to raise $67.4 million in a stock offering priced at $8 per share.

ImmunoGen could bring additional funds if the underwriters exercise a 30-day option to purchase up to 1.35 million additional shares to cover any overallotments. The offering is expected to close on or about May 12.

The money would fund general corporate purposes, which would include developing its pipeline.

The Waltham, Mass-based firm has two products in the clinic that are wholly owned by the company, while its other clinical stage drug candidates are being developed under partnerships.

In addition to lorvotuzumab, the other wholly owned product in ImmunoGen's pipeline is Phase I IMGN388 aimed at solid tumors, for which Johnson & Johnson unit Centocor Inc. has opt-in rights.

Interim data from the dose-escalation Phase I trial that is under way are scheduled to be reported at the annual meeting of the American Society of Clinical Oncology in June.

Immunogen's lead partnered drug candidate, trastuzumab (T-DM1), is expected to be submitted for U.S. marketing approval this year in breast cancer. T-DM1, developed by Genentech Inc. (now part of the Roche Group) is under a collaboration agreement with Genentech.

Under that deal, Roche is responsible for the trial costs, manufacturing and marketing, while ImmunoGen collects milestone payments and royalties.

The company's next most advanced product, lorvotuzumab, is being studied as a treatment for CD56-positive solid tumors. ImmunoGen intends to report interim data at a meeting of the European Society for Medical Oncology. The expansion phase of that trial is under way, and focuses on small-cell lung cancer (SCLC), Merkel cell carcinoma (MCC) and ovarian cancer.

ImmunoGen expects to initiate a Phase I/II randomized trial evaluating lorvotuzumab mertansine for first-line treatment of SCLC by late 2010.

ImmunoGen expects to make a go/no-go decision on the initiation of pivotal testing with the compound in MCC by the end of the year based on findings in the expansion phase of the solid tumor study and on meetings with regulatory agencies.

Orphan drug designation has now been received in the EU and U.S. If ImmunoGen decides to proceed, then the pivotal trial could start in 2011.

In addition, ImmunoGen expects to report interim data at the American Society of Hematology annual meeting in December from one or both of its early stage trials being conducted in CD56-positive multiple myeloma - one assessing lorvotuzumab mertansine as a single agent and one assessing it used with lenalidomide and dexamethasone.

While at ASH, the company also expects to report data from a Phase I weekly dosing trial of SAR3419, which was licensed to Paris-based Sanofi-Aventis SA. Immunogen expects Phase II testing of that product candidate to begin for the treatment of non-Hodgkin's lymphoma in the second half of the year.

ImmunoGen expects two additional compounds to advance into clinical testing in 2010 through the company's collaboration with Sanofi-Aventis. It expects two to four additional product candidates to enter the clinic in 2011, including the next wholly owned ImmunoGen compound.

BT-062 for multiple myeloma, partnered with Biotest, and BIIB015 for solid tumors, partnered with Biogen Idec Inc., are still in Phase I testing.

ImmunoGen had about $42.2 million in cash and marketable securities at the end of March.

It anticipates having cash and marketable securities of between $33 million and $35 million at the end of June, unchanged from previous guidance.