Therapeutic Cancer Vaccines: From The Underwhelming To The Exciting

by: Austrolib

The history of cancer vaccines is a slow one. Aside from the cervical cancer vaccine which vaccinates against the virus (HPV) that causes the cancer, there have been no total successes. Companies have tried for decades to devise a method to get the immune system to recognize and attack cancer, with paltry-to-partial results. There is however, some better news to report. A quick run through of recent relative successes in the field shows that there are some among them that do show some real promise.


Developed by Dendreon (DNDN) and FDA approved in May 2010 with wild fanfare, Provenge is a prostate cancer vaccine that extends patient life an average of 4.1 months according to its phase III trial data. Judging by the Google chart below, it extended the life of the stock for a little over 2 years until in mid 2011 sales were found to be disappointing and the company underwent a restructuring. You can't put a value on 4.1 months of human life and Dendreon deserves credit for providing this gift to prostate cancer patients. But the hype was still way overbought. The stock's Nov. 2 jump from $3.85 to $4.97 however shows that the hope/hype is still there when word came out that Provenge sales, though low, were better than expected. Everyone wants cancer vaccines to do well. Who wouldn't? But be careful. The stock has returned to earth at just over $4.


Developed jointly by Oncothyreon (ONTY) and Merck (MRK), Stimuvax functions similarly to Provenge, where immune cells are primed in vitro to recognize and attack cancer cells. Provenge is specific to prostate cancer and Stimuvax is specific to breast cancer. It has been stuck in phase III trials since June '09, but it has shown a bit more success clinically than Provenge in extending life by an average 13.3 months according to phase IIB data. With wild swings up and down, ONTY has held above its pre June '09 levels of around $2.50 a share to currently just above $4.50. Who knows where it will be if and when approval is secured and initial sales data come in. Experience with DNDN advises caution.


The company behind OncoVEX is BioVex, acquired by Amgen (AMGN) in January 2011 for up to $1B. BioVex took the herpes simplex virus - the one that gives you cold sores - and genetically engineered it to replicate inside tumors, thereby getting attacked by the immune system inside the tumors. The herpes shows a similar protein to the tumor, and as the body attacks it, it also attacks the tumor. OncoVEX is in phase III since '09 as well, but its phase II results are exciting. In a 50 patient trial all diagnosed as terminal, 13 patients responded to treatment, and 8 of those 13 had their cancer completely eliminated by the treatment. BioVex was private when acquired by Amgen, but the lesson here is to never discount a possible buyout. Sometimes cancer vaccines can be too tantalizing for a big player to pass up, especially when 14% of a terminally ill subset are cured.

If it weren't for the fact that AMGN is skirting its all-time highs of $89 a share, this would be a buy. Since acquiring Biovex, the stock has gone up nearly 33%, so I'd say much of the ride is over for now, at least until we get phase III results and/or FDA approval on OncoVEX.

DCVax-L and DCVax-Direct

If you've been following the pattern of this article up to now, we've been progressing from the successful letdowns (Provenge) up the ladder to the most promising in the pipeline. Stimuvax beats out Provenge 13.3 to 4.1 in life extension, and OncoVEX beats out Stimuvax by actually eliminating terminal cancer in 8 out of 50 cases. But if DCVax-L and especially DCVax-Direct are successful, they will go much farther than that.

Developed by microcap Northwest Biotherapeutics (OTC:NWBO), DCVax-L and Direct are both immune system priming vaccines. DCVax-L is designed for brain cancer patients after a tumor has been removed in order to prevent recurrence, injected subcutaneously. DCVax-Direct is designed for inoperable tumors anywhere in the body, injected directly into the tumor (hence Direct). The clinical data on DCVax- L are as follows. The survival rate is 33.8 months and continuing. 9 of 19 patients treated are still alive and most have no evidence of tumor recurrence. Four have survived beyond 45 months since treatment.

DCVax-Direct is one of the most exciting developments in cancer vaccines in my opinion, because unlike any of its competitors, it is designed to treat all cancers anywhere in the body at any stage. The problem though is that NW Bio has $111,000 in cash on hand and has accumulated $288M in losses (page 3) since inception in 1996. They are riddled with debt notes to creditors that are often paid in stock, which means dilution. Basically, NWBO will go through ups and downs for no apparent reason other than a loan being called in. But if you like DCVax's chances and its promise, it's a buy and ignore.

DCVax-Direct trials are just getting started, with NW Bio announcing collaboration with Sara Cannon Research in the UK. Pre-clinical animal studies have shown regression in tumors injected as well in tumors on the opposite side of the body, indicating immune response and memory.

But remember Amgen. BioVex was worth $1B to them. So far DCVax has only cost $288M, and DCVax-L is in phase III as we speak. DCVax-L and DCVax-Direct are basically the same thing, so any good news coming out DCVax-L's phase III trials will have good implications for DCVax-Direct's upcoming trials. This may just catch the attention of a big fish with the resources to pull NW Bio out of its debt hole. Somehow I don't think this company is going anywhere until we find out what DCVax-Direct can really do.

Disclosure: I have no positions in any stocks mentioned, and no plans to initiate any positions within the next 72 hours. I wrote this article myself, and it expresses my own opinions. I am not receiving compensation for it. I have no business relationship with any company whose stock is mentioned in this article.