Speaking of Gleevec....

Long term study results from early targeted therapies are starting to come in. In CML, some 95 percent have survived the cancer after five years due to treatment with Gleevec. (I don't have the pre-Gleevec survival rates, but will try to track them down.)

Also: "Even high-risk patients have close to a 70 percent chance of getting to what we call a complete cytogenetic response, which is an optimal response to the drug. That is still six or seven times better than they ever could have hoped for with the previous standard therapy. So, even for high-risk patients, the likelihood of responding is quite high."

Gleevec is being followed by nilotinib (NVS) and dasatanib (BMS), and will hopefully improve these numbers. What I can't make sense of, though, is the choice of this disease (and these drug targets) as the main focus of a number of other biotech companies.

I understand and appreciate the scientific merit, and there is perhaps a business boost thru the validation that the preceeding therapies provide, but just off the top of my head, I can name several entrants:

Ariad
BMS (dasatanib)
Breakthrough Therapeutics
Chemgenex
Curagen/Topotarget
Innovive
Merck/Vertex
Novartis (Nilotinib)
Structural Genomics
even a DoD funded team at VCU
(plus, I feel like I'm blanking on one or two more)

I really hope this effort results in the eradication of the disease, but surely, even if that is accomplished, 3 to 5 companies will swing hard and create a drug therapy, but ultimately wish that they'd spent their time on something else instead of coming in 3rd or 4th in a 2-horse race.

Is this a call for government regulation of R & D targets? Not quite, especially since I'm a raging libertarian, but you can't help but make parallels to the days before government regulation of the electricity distribution business (early 1900's) when as many as 20 different companies' wires serviced some neighborhoods, pre-regulation.

Targeted therapies: 2006 and beyond

A flurry of 2006 year-end/year-in-review articles cited the strides that targeted cancer therapies made in 2006, specifically:

• The targeted drugs temsirolimus and sunitinib (Sutent) were shown to help people with advanced kidney cancer, which is notoriously difficult to treat, and seemed to have fewer side effects than conventional therapy.
• Another study found that the investigational drug lapatinib (Tykerb) could slow tumor growth in women with an aggressive form of breast cancer that grew despite treatment with trastuzumab (Herceptin).
• Dasatinib (Sprycel) eliminated or decreased the number of abnormal blood cells in people with chronic myelogenous leukemia (CML) who could not tolerate or had become resistant to treatment with Gleevec (imatinib).
• Adding cetuximab (Erbitux) to radiation therapy for head and neck cancer slowed the growth of the cancer and helped patients live longer.

from ASCO summary.

It's a great view when you can take a year-wide view. It is also educational to realize from these articles that targeted therapies are not yet first line therapies (mostly; congrats to ImClone for the recent approval of Erbitux as a first line therapy). It's also easy to forget that many clinicians haven't yet fully integrated targeted therapies into their practice, and that it's articles like these that are helping to spread the news.

A couple of good quotes for the general public emerged from the article linked in the header:

'Targeted therapy is "one of the most exciting new themes in cancer therapy," according to José Baselga, MD, chief of the medical oncology service and director of medical oncology, hematology, and radiation oncology at Barcelona's Vall d'Hebron University Hospital......."Cancer cells are not as resourceful as you would think," explained Baselga. "If you can hit them in 2 critical pathways, you can destroy them, so if you can combine 2 or 3 therapies, you can cause profound cell death."

And some interesting Gleevec stats were revealed by the Guru of Gleevec, Brian Druker: "If you look at the data overall, 18% of patients [on Gleevec] have some progression event at 5 years, and another 5% discontinue because of side effects," he explained.

Gleevec for RA?

Gleevec almost completely prevented the development of the rheumatoid arthritis-like disease in the mice, per Stanford researchers.

Incidentally, good RA summary: "Rheumatoid arthritis is a painful, chronic autoimmune disorder, characterized by inflammation of the lining of the joints. It affects more than 2 million Americans; up to half of those with the disease are disabled after 15 years due to disfigured joints. Standard therapy for rheumatoid arthritis now includes agents that suppress the immune system, but many patients do not benefit from such treatments. They do not get adequate reduction in the symptoms and signs of disease; they may also continue to have damage to their joints or develop side effects that make continued use of such therapies impossible. Thus, new approaches are needed."

ALL therapies: +12% for next 9 years

Decision Resources expects robust growth thru 2015, based on STI approvals.

Also, I didn't realize it, but NVS' Gleevec successor is now dubbed "Tasigna." I wonder why they didn't build off the Gleevec recognition? (Gleesigna?)

Clinical data for Tasigna looks great, per the press releases.

Separately, NVS has announced an intent to file for Tasigna approval before the end of the year.

Handicapping targeted drugs

Though not the main conclusion, this article suggests that dasatanib may be an even better therapy than gleevec for CML patients because dasatanib also inhibits Src signaling in addition to Bcr-Abl.

If so, from a business perspective, BMS just became a bit more valuable. Analysts predict annual sales of $500M for dasatanib (Sprycel), but it if this article is right, may be more like Gleevec's $2.2B annual revenue.

Does this suggest a Novartis buy-out of BMS?

BMS is trading at $24.50.