For years, chemotherapy was the best treatment that the world of medicine had to offer in fighting cancer. That's no longer true. A powerful new class of cancer drugs called immunotherapies has become increasingly effective at treating cancer. These immunotherapies, also known as immuno-oncology (I-O) drugs, harness the body's own immune system to fight cancer. And they're becoming more popular in the research community than you might imagine.

The Cancer Research Institute (CRI) just published the most comprehensive assessment ever of the state of research and development for immunotherapies. This report identified a staggering 2,004 immunotherapies in development or on the market across the world.

For cancer patients, this means there are more experimental I-O drugs than ever before that hold hope for more effective treatment. But there's also a downside to having so many drugs being researched.

Pill opened up with mechanical boxing glove punching cancer cell

Image source: Getty Images.

Impressive numbers

Of the 2,004 I-O drugs in development, 940 were in clinical testing with humans or already approved after having completed clinical testing. The remaining 1,064 drugs were in preclinical testing. These drugs target 303 specific types of cancer. That might seem like an extraordinarily high number, but there are often many types of genetic mutations that cause one broader type of cancer.

For those 940 I-O drugs in clinical testing, the CRI is tracking 3,042 active clinical trials. These trials combine for total enrollment of 577,076 patients. Some of the clinical trials have already fully enrolled, while others are either actively enrolling or plan to begin enrolling in the future.

While there are a huge number of experimental I-O drugs, only 26 have won regulatory approval so far. The first was interferon-alpha back in 1986. The real turning point, though, came in 2011 when Bristol-Myers Squibb (BMY -0.87%) won approval for checkpoint inhibitor Yervoy in treating advanced melanoma. Checkpoint inhibitors block proteins that interfere with the body's immune cells attacking cancer cells. Another checkpoint inhibitor from Bristol-Myers Squibb, Opdivo, is projected to become the No. 2 cancer drug in the world in sales within the next few years.

The numbers from CRI show where the scientific community seems to think the most potential for fighting cancer lies. CRI found 344 cancer vaccines either in clinical development or on the market. These vaccines target either preventing cancer or treating existing cancer. 

Cancer cells with light shining

Cancer cells. Image source: Getty Images.

There are 224 clinical-stage cell therapy I-O drugs. Cell therapy involves putting cellular material into a patient to fight cancer. Novartis' (NVS -0.13%) Kymriah became the first cell therapy to win regulatory approval in August for treatment of B-cell precursor acute lymphoblastic leukemia (ALL). Gilead Sciences (GILD -0.56%), thanks to its acquisition of Kite Pharma, followed closely behind in October with approval of another cell therapy, Yescarta, in treating large B-cell lymphoma.

CRI identified 99 immunomodulators that target T cells in clinical testing or on the market. T cells are immune cells produced in the thymus gland (which is where the "T" comes from in their name). Another 170 clinical-stage immunomodulators are targeting other immune cells or the tumor immune microenvironment.

The more the messier?

All of these numbers are exciting, since they reflect an enormous amount of effort focused on fighting cancer. The CRI report acknowledged this, stating that the development of immunotherapies was "very promising and has the potential to deliver many breakthroughs to change the standard of care of many cancer types."

However, CRI also said that the field was "very crowded, fragmented, and uncoordinated with significant duplication." The crowding is especially true for cancer targets such as PD-1, a checkpoint protein that acts as an on-off switch that tells T cells whether to attack a cancer cell. 

In addition, CRI noted that a key factor behind the explosion in cancer studies was investigator-initiated immunotherapy trials. These investigator-initiated trials tend to be small studies at one site. They're more at risk of not recruiting enough patients to be successful.  

One possible way to address some of these issues, according to CRI, was to implement new clinical trial designs. The organization called for collaboration between biopharmaceutical companies and nonprofit research centers. Such collaborations could help minimize duplication and fragmentation of efforts to find new treatments for cancer.

Cancer and capitalism

There was one other thing from the CRI report that stood out to me: Those 2,004 drugs were owned by 864 companies. Even in China, which has been a communist nation for more than 70 years, businesses lead the way in cancer drug development. The report stated that 46 Chinese companies owned 98 clinical-stage immunotherapies focused on CAR-T (chimeric antigen receptor T cell) development.

Money with pills and syringe

Image source: Getty Images.

All of the 26 immunotherapies available to patients today are owned by biopharmaceutical companies. The most promising cancer drugs that could be game changers are being developed by businesses, and most of them are publicly traded corporations. It's no surprise that the stocks of the most innovative biopharmaceutical companies, such as bluebird bio and Juno Therapeutics, rank among the hottest on the market. 

It seems that better treatment -- and perhaps one day even a cure (or cures) -- for cancer will ultimately come as a result of capitalism. The pursuit of profit, while attacked by some, is probably the best reason to think that there's hope for a world where one day cancer doesn't kill more than 8 million people every year.