What happened

Shares of Iovance Biotherapeutics (IOVA -6.29%) jumped as much as 47.6% today after the company reported interim data from ongoing clinical trials for two drug candidates. Both experimental treatments use tumor-infiltrating lymphocytes (TIL) to harness an individual's immune system to target and attack cancer cells.

The biopharma announced that LN-145 achieved an overall response rate (ORR) of 44% for advanced cervical cancer patients. By comparison, Keytruda from Merck has an ORR of 14% in the same patient population. Meanwhile, LN-144 (lifileucel) maintained its previously observed ORR of 38% in advanced melanoma and delivered a disease control rate of 76% at the 7.4-month median follow-up.

As of 2:16 p.m. EDT, the stock had settled to a 34.3% gain.

A businessman tossing cash money in the air.

Image source: Getty Images.

So what

Today's news is a big deal for Iovance Biotherapeutics. While early-stage clinical results can be promising, it's always important for the glimpses of efficacy and safety to hold up in later-stage studies. The interim data for LN-145 are part of a phase 2 trial, while the update for lifileucel is from a phase 3 trial.

What's more, the company may only be scratching the surface of what TILs can do. The studies reporting updates today involve just a single dose of treatment in two cancers with poor prognosis. That suggests there's ample room for fine-tuning in the solid tumor landscape, such as combination therapies or patient-specific TILs.

Progress is being made on that front. Iovance Biotherapeutics announced that the first patient was dosed in a phase 2 trial evaluating a combination therapy of lifileucel and Keytruda. It's also exploring next-generation TIL products as therapies for solid tumors that rapidly mutate, a common feature of advanced melanoma.

Now what

When Iovance Biotherapeutics made a bet on TILs years ago, it was an unusual move given the CAR-T craze. But the strategy is certainly showing promise now. Investors will need to remain patient, as the company doesn't expect its most advanced clinical trial (lifileucel in advanced melanoma) to reach full enrollment until early 2020. That said, this $1.8 billion company is one to watch in the immunotherapy space.