UCSF doctors create new class of drugs to battle cancer

SAN FRANCISCO (KGO) -- Bay Area researchers are fighting back against a particularly deadly form of cancer and they're doing it with a new generation of drugs.

These drugs enlist the body's own immune system to wage war on tumors.

Grade school teacher Brian Landers is grateful to be back in the classroom after battling an often deadly form of cancer.

It's a victory he owes in part to an emerging, cutting edge treatment. "I feel like the poster child for what these types of therapies can do," Landers said.

After being diagnosed with Stage 4 melanoma, Landers was referred to Adil Daud, MBBS.

Daud and his team at UCSF have been working with a new class of cancer drugs. Their purpose is to prevent the melanoma tumors from using a specific trick to hide from our immune system and it's protective T-cells. "When your T-cell goes in and tries to kill a melanoma tumor, the tumor produces something called PD ligand. It'll bind to something called PD-1 on the surface of a T-cell and turns off that T-cell," Daud said.

But new-generation drugs like Keytruda from Merk are designed to prevent the PD molecules from reaching the T-cell and turning it off. The strategy is getting increased attention since former President Jimmy Carter announced that his melanoma appears to be in remission after treatments that included Keytruda. "What we can tell is that many of these responses are long lasting. PD-1 inhibitors can produce a responses in maybe 30 percent to 40 percent of patients," Daud said.

In Landers' case, scans showed one tumor completely vanished, leaving only scar tissue.

Daud said researchers are now working on new combination therapies that may soon help PD-1 inhibitors work even more effectively.

If successful, Landers believes they could eventually unleash a new era, where our own immune systems become the ultimate resource for fighting cancer. "Exactly what everybody's immune systems are capable of doing," Landers said.

The doctor said there's evidence that our body's cancer-fighting cells may even adjust their behavior under the new therapy and continue to the tumors even after the drug regimen is over.

Written and produced by Tim Didion.