Reminder: Pharmboy is available to chat with Members, comments are found below each post.
Monoclonal Antibodies (Part 2)
(See also: Monoclonal Antibodies Part 1)
Courtesy of Pharmboy
In Part 1 of Monoclonal Antibody Companies, I highlighted a leader in the field, Seattle Genetics (SGEN). It's technology incorporates monoclonal antibodies (mAb), and also allows for having a drug ‘tagged’ on the mAb, so that when the mAb attaches to a cell, it is ‘ingested’ into the cell, and the drug is released. The antibody-drug combination is called an antibody-drug conjugate (ADCs). ADCs are "empowered" antibodies. They are designed to use the targeting ability of the antibody to precisely deliver the toxic drug where it's needed, increasing its effectiveness and decreasing side effects.
Think of the technology as a bunker buster bomb, that is guided by a laser, hits its target, penetrates, and then destroys all from within. Seattle Genetics has licensed its technology to several companies. Other companies are involved in this kind of research as well.
Antibodies are used by the immune system to clear pathogens from the body. The antibody protein is in the shape of a Y, where the trunk is the effector region (similar in most antibodies) and the ends of the Y are the variable regions (paratope) that bind the pathogen (antigen).
Antibodies are produced by B-cells and used by the immune system to identify and neutralize foreign material such as bacteria and viruses. There are several types of antibodies made for the defense of the body. (More here)
ImmunoGen, Inc. (IMGN, $12.92) was a pick several years ago at Phil's Stock World after the FDA declined to give it (and Roche) accelerated approval, even though its treatment for breast cancer worked (here). IMGN uses a similar technology to SGEN, coined Targeted Antibody Payload (TAP). TAP is simply a monoclonal antibody which carries a highly "toxic payload” of anti-cancer drugs to the cancer site. Using TAP allows toxic cancer drugs to be better tolerated by the patients because it minimizes the side effects of the drugs.
Trastuzumab-DM1, or T-DM1 for short, is for women with advanced HER2-positive breast cancer who have previously received multiple HER2-targeted medicines and chemotherapies, including Genentech’s Herceptin. A mid-stage study of the drug showed that it shrank tumors in women with HER2-positive breast cancer, a form of the malignancy in which the protein, human epidermal growth factor receptor 2, promotes the growth of cancer cells. Unfortunately, this lead drugs is licensed to Roche, and IMGN's royalties are light at 5% (here).
IMGN has an exciting pipeline, including:
1. Lorvotuzumab mertansine (IMGN901) is a CD56-targeting TAP compound wholly owned by ImmunoGen. It is a potential new therapy for treating small-cell lung cancer (SCLC) and other cancers that express CD56. From IMGN's website: "SCLC is a highly aggressive cancer that almost universally expresses CD56 and has limited treatment options today. These factors, taken together with IMGN901 preclinical and clinical findings, led us to pursue SCLC as its lead indication. We are evaluating IMGN901 for first-line treatment of SCLC in our NORTH trial. This Phase II assessment evaluates IMGN901 used together with etoposide/carboplatin (E/C) – a standard care for this cancer – to determine if the addition of IMGN901 to E/C meaningfully improves duration of progression-free survival (PFS). Patients enrolled in the NORTH trial receive E/C either with IMGN901 or by itself." The dose of IMGN901 was established in a Phase I study.
"IMGN901 is being assessed for MM [multiple myeloma] used in combination with lenalidomide plus dexamethasone, a standard care for this cancer. Promising data were presented at ASCO in June 2011 from the dose-finding portion of this Phase I trial. We expect to report final data from this trial at a medical meeting in late 2012. Data were presented at ASH this past month (here), and the drug shows encouraging results."
2. IMGN529 is being investigated to treat B-cell malignancies such as non-Hodgkin’s lymphoma and chronic lymphocytic leukemia. IMGN529 preclinical data have been reported at a number of major scientific conferences. This scientific poster includes data on the expression of IMGN529’s target, CD37, on B-cell cancers, IMGN529’s mechanisms of action, and its activity in preclinical models. This is early on, but CD37 is an interesting target for cancer. (More here)
IMGN has licensed its technology to Biogen Idec, Sanofi, Amgen and Roche. I think the stock can move into the $15-20 range in the next year or two and am going to add 100 shares to Pharmboy's Virtual Portfolio on Monday.
Disclosure: I do not own any shares of IMGN, but may purchase shares or options at any time.
