NEW YORK – HighField Biopharmaceuticals said on Tuesday that it will begin studying the investigational treatment HF158K1 in patients with HER2-low or HER2-positive advanced solid tumors.
The US Food and Drug Administration cleared the firm's investigational new drug application for a Phase I trial of HF158K1 in solid tumors, including breast, bladder, pancreatic, ovarian, stomach, colon, prostate, lung, uterine, and cervical cancers. Investigators will begin enrollment in the US, China, and other countries this summer, aiming to include 24 patients in the Phase Ia dose-escalation portion followed by up to 60 patients in the Phase Ib dose-expansion portion. HighField aims to assess the drug's safety and preliminary efficacy.
In the trial, HER2-positive patients will be those with 2+ or 3+ immunohistochemistry (IHC) scores or positive via in situ hybridization (ISH) testing. HER2-low patients will be those with 2+ IHC scores and a negative ISH result or those with 1+ IHC scores. Patients must have unresectable or metastatic advanced solid tumors that are refractory to standard treatments.
HF158K1 involves what HighField calls an immunoliposome, which is designed to bind to cancer cells expressing the target and deliver a cytotoxic drug to those cells. In this case, the drug is the chemotherapy doxorubicin and the target is HER2.
The drug's mechanism is similar to antibody-drug conjugates, but Hangzhou, China-based HighField believes HF158K1 has advantages in that it can deliver larger doses of the active drug and can target tumor cells using multiple antibodies. This could translate to lower toxicities and greater efficacy, according to the firm.
"The FDA's clearance of this IND is … recognition our immunoliposomes may offer effective alternatives to most current HER2 drugs that cannot target low HER2 tumors," HighField CEO Yuhong Xu said in a statement. "HF158K1 is designed to bind and deliver the chemotherapeutic doxorubicin to tumor cells at even very low HER2 expression levels."