Looking Back on the Week

I didn’t really have one burning issue to blog about this week, so I am going to pick over a few things that caught my eye.

The first was, perhaps predictably, news about more lay-offs, this time at South San Francisco biotech Exelixis. I went through a series of emotions as I read about this story. Initially, it was “oh no, not another one”, then realizing it was a biotech, I thought it was that last hail mary push for the drug candidate that would either break them or make them rich. But looking closer, we find that Exelixis is not exactly a start-up any more and have been around since 1997, have had extensive collaborations with multiple different partners in the industry and have just reached a point where they need to concentrate their resources on their remaining development goals, the main ones coming from collaborations with GSK and Sanofi-Aventis. I can appreciate the need to concentrate, although it is not exactly a great reward for the work put in by their discovery team that allowed them to have all these compounds in their pipeline to advance. I trust they got good severance and that Exelixis will restart their discovery efforts once their current pressures are eased, but I do wonder how many of their old discovery chemists would return if asked.

I also came across several articles this week talking about new approaches to medical problems. A new way to treat HIV published in Nature Medicine by a Canadian-U.S. collaboration implicates two molecules, PD-1 and IL-10, in shutting down T-cells and allowing for HIV infection. Immunotherapy could thus be used to help restore the immune function to an HIV-infected patient, in conjunction with other therapies.

Prostate cancer is notoriously difficult to treat and it has been found that part of the problem is that anti-androgen therapies that attack the cancer early on by attacking the male hormones that the cancer needs to grow lose their potency, allowing the cancer to grow again. Michael Karin and team at UC San Diego studied the problem of drug resistance in mice and have found that a signalling molecule called lymphotoxin is secreted that activates an androgen independent cell growth pathway. Their goal now is to see if this happens in humans, allowing us to potentially block the onset of resistance.

My favorite new medical treatment came to me via the Pharma Conduct blog, the Cyberknife. It is essentially a robot that can shoot very narrow x-ray beams, excising cancerous growth with beyond surgical precision. And because it is so precise, much higher doses of radiation can be delivered and the number of treatments and side effects are much reduced. So I recommend you check that out.

Finally, a neat way to help fund research into AIDS, malaria and tuberculosis being implemented by a group called MassiveGood. They are aiming to offer travellers a chance to donate some small amount – say $2 – by adding it to their hotel, flight or rental car bill. The New York Times covered the campaign, and it looks like it might raise some quite respectable amounts of money, if European versions of the program can be emulated. Good luck to them.

New Cancer Treatments

It has been a little while since I did anything on this blog but add links into my job search pages, but a couple of articles caught my eye this week. One makes use of insulin growth factor (IGF) with a chemotherapy agent attached to it, as a Trojan Horse to target the cancer cells. The other uses minicells generated from mutant bacteria, which then deliver a payload of a chemotherapy agent to the site in question via an antibody.

The insulin therapy, reported in the Star-Tribune, talks about a company called IGF Oncology, which has a great story and a promising therapy. It is not quite clear from the article exactly how it works, but it appears to be targeting the IGF receptor (I found this blog on that subject), which can help a cancer cell survive attack from chemotherapy. While the initial results from their study are encouraging, the potential for side effects is still there, as normal cells also have the IGF receptor. Raising the money needed for a further (much more expensive) study will be challenging.

The minicells, reported in the New York Times, are another approach which seems to be more advanced in its path toward validation. The bacterial minicells are loaded with something that will attack the cancer cells or interfere with multidrug resistance. They are also coated with antibodies, allowing them to reach the cancer cells selectively. When presented with a bacterial infection, the cancer cells respond by attacking and destroying the minicell, which releases its payload at the site of the cancer.

This is a very neat idea and results in animals (mice, dogs and monkeys) have been spectacular – more than 20 dogs with advanced brain cancer were treated and all of them responded with some in remission. Given how difficult it is to treat brain cancer, this is impressive.

A lot of cancer therapies have been harsh. The patient is dying, so the fact that the drug is hurting the patient slightly less than the cancer is seen as an improvement. Though there is a long way to go yet, with these or other treatments, a goal of more selective and less destructive therapies is definitely a worthwhile target.