Canada's OpenAI-backed startup Biossil Labs has extended its pharma shopping spree with a deal worth up to $91 million for Theriva Biologics' deprioritized early- to mid-stage portfolio of antibiotic-degrading enzymes.
For an upfront payment of $350,000, Maryland-based Theriva will turn over its slate of drug candidates designed to protect patients receiving an antibiotic from contracting further infections. The deal could potentially pull in $3 million via regulatory milestones and up to $88 million in worldwide net sales achievements. Theriva would also be eligible for up to $250 million in royalties at a rate of low single digits, according to a press release.
The portfolio is led by the prophylactic therapy SYN-004, also known as ribaxamase, which Theriva has taken through a phase 2b trial in patients receiving an antibiotic for lower respiratory tract infection, demonstrating gut microbiome maintenance and recovery, reduced incidence of Clostridioides difficile infection and lower pathogen rates overall. The company is also handing over two preclinical oral options, including the ribaxamase reformulation SYN-007 and another antibiotic degrader called carbenemase, or SYN-006.
Since exiting stealth in April with a $70 million investment from artificial intelligence giant OpenAI and venture capital firm Founders Fund, Biossil has specialized in purchasing drug candidates that have underperformed. The idea is to give these cast-offs a second shot at success based on AI recommendations. In July, Biossil signed a $105 million deal for a failed antibiotic from Summit Therapeutics, and last year purchased dismutase mimetics from Galera Therapeutics in a similar $105 million biobucks agreement. In addition, the company has picked up the sickle cell candidate rivipansel from Pfizer.
“Gut dysbiosis, antibiotic-resistant colonization and opportunistic infections in vulnerable patients represent important unmet needs that recommend we advance this portfolio of antibiotic-degrading enzymes with rigor and equipoise,” Biossil Chief Scientific Officer Alexander Mosa, MD, Ph.D., explained in the release.
Biossil will continue a phase 1b/2a study of Theriva's SYN-004 in patients susceptible to graft-versus-host disease and other infections that can crop up along with antibiotic treatment during hematopoietic cell transplant. Theriva had paused enrollment in the study after completing two of the three planned cohorts.
Theriva made the decision to deprioritize SYN-004 last year to focus its limited cash supply on VCN-01, an oncolytic adenovirus in early- to mid-stage trials for conditions including metastatic pancreatic ductal adenocarcinoma and refractory retinoblastoma. Biossil is betting that the drug candidate can fill a critical gap for patients at high risk of infection due to exposure to antibiotics and the resistance that can accompany them.