What happened

Shares of TG Therapeutics (TGTX 1.23%) gained over 35% last month, according to data provided by S&P Global Market Intelligence. The pharma stock ended the year on a high note thanks to two impressive data presentations at the Annual Meeting of the American Society of Hematology (ASH).

The company is developing two separate triple-combination therapies as treatments for relapsed (meaning a cancer has returned after treatment) or refractory (meaning a cancer was resistant to treatment) non-Hodgkin's lymphoma (NHL) and chronic lymphocytic leukemia (CLL). Both triple combinations achieved very high response rates in small, early-stage studies. 

That was enough to propel shares to a 170% gain in 2019.

A businessman tossing cash into the air.

Image source: Getty Images.

So what

Combination therapies are becoming increasingly common in drug development. If multiple active pharmaceutical ingredients prove safe together, then combination treatments can benefit from multiple or synergistic modes of action. TG Therapeutics is all-in.

Both of the company's triple-combination therapies in blood cancers contain a proprietary duo of ublituximab (an experimental monoclonal antibody) and umbralisib (an experimental small-molecule inhibitor of PI3K delta and CK1 epsilon, two proteins involved in cellular growth). The combination is known as U2. 

In the triple-combination therapy of U2 and the approved cancer drug venetoclax, all 13 CLL patients in the study responded to treatment. All nine evaluated in time for the ASH data cutoff had undetectable levels of minimal residual disease in their blood, while seven met that benchmark in their bone marrow.

In the triple-combination therapy of U2 and a proprietary asset called TG-1701, six of seven people with NHL or CLL responded to treatment at the lowest dose of TG-1701 tested. 

Now what

TG Therapeutics could be onto something with its triple-combination drug candidates in blood cancers. Of course, the results presented at ASH are from small, early-stage studies. Investors will need to see these impressive results supported by larger clinical trials in the next few years and know that those successfully treated to date maintain their responses for the long haul.