Drug accelerator Cydan unveiled its third orphan drug company: Tiburio Therapeutics, which starts life with $31 million in series A funding and a pair of clinical-stage compounds licensed from Ipsen. The series A will support its lead asset through phase 2 in non-functioning pituitary adenoma (NFPA), a type of tumor of the pituitary gland that has no approved therapeutic options.
The candidate, TBR-760, is a dopamine-somatostatin chimeric molecule that has been shown to inhibit NFPA cell proliferation, and so, could potentially stop tumor growth, or shrink tumors, said Tiburio CEO Abraham Ceesay. Currently, NFPA patients are treated with transsphenoidal surgery—a procedure through the nose and sphenoid bone—and/or radiation to remove the tumor. However, Ceesay said, about half of the patients that undergo these procedures still have tumor remnants in their brain, which could grow later on and necessitate another surgery.
A therapeutic approach could spare NFPA patients from this surgery. Ceesay envisions the patient population for TBR-760 in two buckets—the approximately 50,000 patients who have undergone surgery and have active tumor remnants in their brain and the 5,000 newly diagnosed patients each year who may be able to take the drug before needing invasive surgery.
Patients in the first group could receive TBR-760 as they continue to be monitored for tumor growth, Ceesay said. This could stop that growth, or even shrink tumors, helping those patients avoid further surgery and/or radiation. As for the new patients, Tiburio thinks there may be an opportunity to drug them before they undergo surgery.
“It’s something we’re really going to have to evaluate in our development program to understand what the effects are prior to transsphenoidal surgery,” Ceesay said.
Tiburio will start phase 2-enabling studies for TBR-760 immediately and planning to start a phase 2 trial in NFPA patients in the second half of 2019. The series A, drawn from New Enterprise Associates, Longitude Capital, Lundbeckfond Ventures,and Alexandria Venture Investments, will also cover work on a second asset, TBR-065, which the company is developing for “several rare endocrine conditions.” But the timeline for that drug is more flexible, as Tiburio’s initial focus will be pushing TBR-760 through the clinic.
The Cambridge, Massachusetts-based startup is launching with a “lean group of experts” in the endocrine space, including folks who had worked on the compounds at Ipsen, but will be expanding its team as it progresses through the clinic: “We are going to be actively building out our clinical development team both in terms of overall clinical strategy and clinical operations, as well as regulatory function,” Ceesay said.
Cydan launched its first rare disease startup back in January 2015—Vtesse raised a total of $42 million in its series A to work on its treatment for Niemann-Pick disease type C1 disease and was later bought out for $200 million. The accelerator followed up with the April 2016 launch of Imara, which is developing a new treatment for sickle cell disease.