Whether or not you're an avid follower of the health-care sector, there's always something intriguing and innovative going on.

Over the past couple of years we've witnessed one tissue engineering company develop a platform that may one day soon manufacture human organs, while also observing the determination of a handful of biopharmaceutical companies as they took on global killer hepatitis-C and practically eradicated the disease in trials. In other words, there's always something to be excited about as an investor, even if the overall market doesn't always agree.

Earlier this week, however, we had one of those potentially jaw-dropping moments that makes the biotech sector such an exciting place to follow and invest.

Source: EMD Group.

Making medical history
According to a study conducted by the Mayo Clinic, Stacy Erholtz, a sufferer of multiple myeloma (a cancer of the bone marrow) which had spread throughout her body, experienced a complete remission (i.e., no detectable levels of cancer found) after receiving a gargantuan dose of the measles vaccine which, under normal dosing circumstances, could have inoculated 10 million people.

As Dr. Stephen Russell, a molecular medicine professor who led the study for Mayo Clinic, was quoted as saying last week in an interview with the Star Tribune, "It's a landmark. We've known for a long time that we can give a virus intravenously and destroy metastatic cancer in mice. Nobody's shown that you can do that in people before." The Mayo Clinic's next step is to study this so-called "measles blitzkrieg" in a larger number of patients to determine if it'd be effective in other types of cancer, as well as establish what level of virus might be needed to break down the natural defense mechanism of cancer cells in order to overwhelm them.

...But keeping it in context
Of course, we have to take into consideration two other major aspects of the Mayo Clinic study. First, it was a two-person study, and the other individual whose metastatic cancer was found primarily in their muscles didn't experience a complete remission like Stacy Erholtz. This could mean that the measles vaccine super-dose isn't an effective option on all cancer types, or it could be based on a person's genetic makeup.

The other factor to consider here is that while the super-dose of the measles worked on Stacy Erholtz, there are a ton of unknowns still left for researchers to explore, such as cancers' defense mechanism threshold, and why the measles vaccine so selectively worked on Erholtz' cancer but not on the other patient. Researchers are realistically still a ways off from having the answers to these questions. 

Source: EMD Group.

This could be the start of something powerful
Regardless of whether it takes three months or five years for Mayo Clinic researchers to begin filling in the blanks to its study, the results this week really highlight why researchers and investors might want to take vaccination and immunotherapeutic cancer solutions seriously. Putting that into context once again, one positive result doesn't mean we've found an end-all cancer cure, but it does demonstrate that the science behind treating cancer with vaccinations, whether it be through injectable viruses or immunotherapeutic boosts, could prove quite effective.

A few names to watch over the coming years
Obviously, it's worth keeping a watchful eye on global pharmaceutical giant Merck (NYSE:MRK) which manufactures a measles, mumps, and rubella virus vaccine (MMR). It remains to be seen if the measles virus given in large doses can be effective in other cancer scenarios; however if it is Merck may need to be prepared to supply an abundance of its vaccine.

But, I really feel this news places the spotlight on what's going on within the cancer immunotherapy space, whereby biopharmaceutical companies are utilizing the body's own defense system to enhance its chance of fighting cancer. Like the measles super-dose, this might not be an end-all cure, but it does represent an intriguing new option for patients and physicians that could improve patient care and quality of life.

Upcoming studies from Galena Biopharma (NASDAQ:GALE) and Peregrine Pharmaceuticals (NASDAQ:PPHM) are two in particular I'd certainly suggest monitoring.

Breast Cancer Cell

Breast cancer cell, Source: National Cancer Institute, Wikimedia Commons.

Galena Biopharma's prized experimental immunotherapy is NeuVax, an adjuvant therapy designed to help HER2-negative breast cancer patients (the most common form of breast cancer) remain disease-free. Breast cancer is the second-most diagnosed cancer in the U.S. each year, so developing effective therapies to derail a relapse is incredibly important. In its final phase 2 results, at the 60-month mark just 5.6% of the NeuVax intent-to-treat group had a cancer relapse compared to 25.9% of the placebo group. This 78.4% recurrence reduction difference has given investors and breast cancer patients significant hope that Galena's phase 3 results may prove successful. 

Peregrine Pharmaceuticals' bavituximab is another exciting therapy which in mid-stage trials more than doubled median overall survival as a second-line non-small cell lung cancer therapy (12.1 months compared to 5.6 months for the placebo). Bavituximab works by blocking an immunosuppressive molecule found on the outside of cancer cells which allows them to go undetected by the immune system. The thought here is if they can be spotted easier, then the patients' immune system has a better chance to fight the disease. Phase 3 trials of bavituximab initiated enrollment back in December.

Yet, similar to the unknowns surrounding the Mayo Clinic's "measles blitzkrieg" trial these two experimental drugs aren't without their own unique risks. Historically smaller cancer-focused biotech companies have fared very poorly in phase 3 trials or have failed to garner the approval of the Food and Drug Administration when filing for a new drug application. In addition, many immunotherapy vaccine developers (not just Galena and Peregrine) are fairly small in nature and have limited funds for research. Although Galena has Abstral approved as a breakthrough cancer pain therapy, both it and Peregrine are burning cash at the moment and could struggle to survive if NeuVax and bavituximab aren't eventually approved.

This is truly an exciting time
Still, the landscape of vaccine-based therapy is changing rapidly, piquing investor interest, but more importantly lending hope to cancer patients, and the friends and family of those patients, that more effective treatments may be on the way. The Mayo Clinic's landmark study may be a long way from having all the answers, but the simple point that we're finally starting to ask the right questions is a victory in and of itself.

Sean Williams has no material interest in any companies mentioned in this article. You can follow him on CAPS under the screen name TMFUltraLong, track every pick he makes under the screen name TrackUltraLong, and check him out on Twitter, where he goes by the handle @TMFUltraLong.

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