FDA Approves Clinical Testing of Minerva’s CAR T-cell Therapy for Metastatic BC

Minerva Biotechnologies will soon start the first human trials testing its investigational therapy huMNC2-CAR44, a CAR T-cell immunotherapy intended for breast cancer that has spread to other parts of the body.

The announcement comes after the U.S. Food and Drug Administration (FDA) approved the company’s investigational new drug (IND) application for the treatment, clearing it for clinical testing. The technology targets the protein MUC1*, associated with solid tumor cells. Minerva plans to start the first clinical studies before the end of 2019.

“We are delighted that we will soon be able to begin human clinical trials for metastatic breast cancer,” Cynthia Bamdad, Minerva’s CEO, said in a press release.

“Over 95% of breast cancers are positive for MUC1*, and this cancer immunotherapy has the potential to bring hope to the many thousands of patients battling this terrible disease,” Bamdad added.

Chimeric antigen receptor (CAR) T-cells are a new approach to fighting cancer, which harnesses and strengthens the body’s natural defenses to attack tumors. It involves collecting a patient’s own T-cells — immune cells which can directly kill targeted cells — and genetically engineering them in the lab to selectively recognize and kill cancer cells. After modification and expansion in the lab, the cells are injected back into the patient to fight the cancer.

This strategy has been successful, and has been approved for certain advanced blood cancers, including some forms of leukemia and lymphoma. It has led to remarkable responses in some children and adults for whom other treatments had stopped working. Two CAR T-cell products are currently approved by the FDA – Novartis‘ Kymriah (tisagenlecleucel) and Kite Pharma‘s Yescarta (axicabtagene ciloleucel).

However, up to now it has remained unclear if an identical strategy will ever be effective against solid tumors like breast cancer.

Minerva’s CAR T-cell technology — called huMNC2-CAR44 — targets MUC1* (pronounced as muk one star), a protein present at the surface of more than 75% of solid tumor cells.

Researchers from Minerva discovered that a protein normally present in healthy cells — MUC1 — is cleaved or split in tumor cells. This gives rise to a shortened form, which Minerva gave the name MUC1*.

Unlike the full-length protein, MUC1* exposes a binding site for a powerful growth factor. Minerva researchers have found that when this factor binds to MUC1*, it relays signals that promote the rapid growth of cancer cells. It also promotes the emergence of resistance to common anti-cancer therapies.

Minerva’s CAR T approach is designed to modify T-cells in the lab to display on the surface an antibody that selectively binds to MUC1* and homes in T-cells to tumors expressing the marker.

The company has gathered evidence that targeting MUC1* will work to effectively fight tumor cells. Researchers saw that inhibiting MUC1* can block cancer cell growth and reverse resistance to anti-cancer medications, including Herceptin (trastuzumab) — a targeted therapy used to treat HER2-positive breast cancer.