Freeline Raises $120M for Pivotal Trial of FLT180a, a Gene Therapy Candidate for Hemophilia B

Freeline has raised $120 million to support the launch of a pivotal clinical trial of FLT180a, the company’s lead gene therapy candidate for the treatment of hemophilia B.

FLT180a uses AAVS3, Freeline’s proprietary adeno-associated virus (AAV) protein shell, or capsid, to infect human liver cells to deliver a functional version of F9 — the gene that provides instructions to make the blood-clotting protein called factor IX (FIX), which patients with hemophilia B are missing.

A Phase 1/2 trial (NCT03369444) called B-AMAZE is investigating the safety and effectiveness of single, increasing doses of FLT180a in adult men with moderate-to-severe hemophilia B. The study, which started recruiting participants in the U.K., has now opened sites in the U.S. and Italy. More information about locations is available here.

Previous data from the first eight men treated in B-AMAZE showed that FLT180a was able to increase and maintain FIX activity within a normal range, when given at a dose of 9.75×10¹¹ vector genomes per kilogram (vg/kg).

An open-label Phase 2/3 long-term extension study (NCT03641703) enrolling patients who participated in B-AMAZE and other trials of FLT180a also is ongoing. Sponsored by Freeline, this study plans to evaluate the safety and effectiveness of FLT180a in 50 patients for up to 15 years.

Funding proceeds also will be used to support the company’s ongoing Phase 1/2 clinical program of FLT190 for Fabry disease, and to advance the development of two other gene therapy candidates: FLT210 for hemophilia A and FLT200/201 for Gaucher disease.

In addition, funds also will be used to expand the company’s current manufacturing capabilities and to further develop its proprietary gene therapy platform.

“The potential of gene therapy to change patients’ lives has never been greater and we are delighted to have leading U.S. and European biotechnology investors join us in this extended Series C financing,” Theresa Heggie, CEO of Freeline, said in a press release.

“It comes at an exciting time for Freeline with our lead program in hemophilia B progressing through clinical development, and with promising programs behind that, including a gene therapy treatment for Fabry Disease in the clinic and for Gaucher Disease and hemophilia A in late preclinical development,” Heggie said.

With the closing of this financial round, Syncona’s previous investment of $40 million in Freeline now counts with an additional $80 million of new cash capital.

“Freeline’s product candidates have significant potential to achieve functional cures for patients across a broad array of systemic diseases and we are very pleased with the progress the company has made to date,” said Chris Hollowood, chief investment officer of Syncona and chairman of the board of directors of Freeline.

“We are focused on maximizing its ambition to develop gene therapy product candidates, and are pleased with the outcome of this funding round which brings in like-minded partners to support the company as it continues to scale and drive multiple programmes through the clinic. We are hugely excited about its potential to transform the lives of patients and their families,”  Hollowood added.

The financing was led by Novo Holdings A/S, Eventide Asset Management, and Wellington Management Company, with additional support from Cowen Healthcare Investments, Acorn Bioventures, and Ample Plus Fund.