Brii Biosciences is putting all its chips on hepatitis B, hoping that potential partners will show an interest in picking up the remainder of a wide-ranging pipeline that includes HIV, lung disease and depression programs.
The focus of the Chinese biotech’s attention is now BRII-179, a protein-based immunotherapeutic that Brii licensed from VBI Vaccines. The candidate is in a pair of phase 2 trials to see whether it could form part of a “potential functional cure regimen for the treatment of chronic HBV infection.”
The therapy, which is designed to induce enhanced and broad B-cell and T-cell immunity, is being studied in combination with either elebsiran, a subcutaneously administered hepatitis B virus (HBV)-targeting siRNA licensed from Vir Biotechnology, or pegylated interferon alpha (PEG-IFNα)-based therapy.
“2023 was a pivotal year for Brii Bio, with key insights received from multiple phase 2 combination studies," Brii’s CEO Zhi Hong, Ph.D., said in a full-year earnings release.
“With BRII-179 we have a strategy to assess and enhance HBV patients’ intrinsic immunity, targeting therapies to those most likely to respond while sparing others from poorly tolerated regimens,” the CEO said. “These are important breakthroughs informing our late-stage clinical combination trials.”
The company also has other clinical studies ongoing looking at both elebsiran and tobevibart, an HBV-neutralizing monoclonal antibody designed to block entry of all 10 genotypes of HBV into hepatocytes.
But Brii’s newfound enthusiasm for HBV is coming at a cost for the rest of the biotech’s pipeline. In the same earnings release, the company revealed that in order to “prioritize resources to focus on the clinical and commercial development” of its HBV portfolio, the biotech is now “pursuing partnership opportunities” for essentially every non-HBV program.
That includes BRII-693, a treatment for serious gram-negative infections that the biotech globally licensed from Qpex Biopharma only last July. Brii had been gearing up to launch a phase 3 registrational trial in hospital-acquired bacterial pneumonia and ventilator-associated bacterial pneumonia next year. But the status of the program in today’s release is that the company is “seeking strategic funding partners to expedite development.”
Also awaiting external interest is BRII-753, which has completed phase 1 studies to explore its use as a combination treatment option for HIV patients. Additionally, Brii had initiated preclinical work to see if BRII-753 could be used as a subcutaneous injection to offer pre-exposure prophylaxis for HIV.
They will be joined on the back burner by two long-acting injectable therapies for neurological conditions. One is BRII-296, which is awaiting a readout from a phase 2 trial in postpartum depression in the second quarter of the year. The other is BRII-297, which is undergoing a phase 1 study for anxiety and depressive disorders with data due in the second half of the year.
It’s perhaps less of a surprise that Brii is leaving epetraborole for someone else to invest in. Last month, Brii’s partner AN2 Therapeutic announced it was voluntarily pausing enrollment in the phase 3 portion of a study of the bacterial leucyl-tRNA synthetase inhibitor for treatment-refractory mycobacterium avium complex lung disease “pending further data review.”
Brii entered 2024 with 2.6 billion Chinese yuan ($376 million) in cash and equivalents, which it expects to fund operations through 2027.