Odevixibat is a potent, non-systemic ileal bile acid transport inhibitor (IBATi). Albireo is developing odevixibat to treat rare pediatric cholestatic liver diseases, including progressive familial intrahepatic cholestasis, biliary atresia and Alagille syndrome.
With normal function, approximately 95 percent of bile acids released from the liver into the bile ducts to aid in liver function are recirculated to the liver via the IBAT in a process called enterohepatic circulation. In people with cholestatic liver diseases, the bile flow is interrupted, resulting in elevated levels of toxic bile acids accumulating in the liver and serum. Accordingly, a product capable of inhibiting the IBAT could lead to a reduction in bile acids returning to the liver and may represent a promising approach for treating cholestatic liver diseases.
The randomized, double-blind, placebo-controlled, global multicenter PEDFIC 1 Phase 3 clinical trial of odevixibat in 62 patients, ages 6 months to 15.9 years, with PFIC type 1 or type 2 met its two primary endpoints demonstrating that odevixibat reduced serum bile acids (sBAs) (p=0.003) and improved pruritus (p=0.004). Additionally, interim results from PEDFIC 2, an open-label Phase 3 extension study, demonstrate continued and durable reductions in sBAs, improvements in pruritus assessments, and encouraging markers of liver and growth function in patients treated up to 48 weeks. Across both studies, odevixibat was generally well tolerated, and treatment-emergent adverse events were mostly mild or moderate. The Company intends to complete regulatory filings in the EU and U.S. no later than early 2021, in anticipation of regulatory approval, issuance of a rare pediatric disease priority review voucher and launch in the second half of 2021.
Odevixibat is being evaluated in the ongoing PEDFIC 2 open-label trial (NCT03659916) designed to assess long-term safety and durability of response in a cohort of patients rolled over from PEDFIC 1 and a second cohort of PFIC patients who are not eligible for PEDFIC 1.
Odevixibat is also currently being evaluated in a second Phase 3 clinical trial, BOLD (NCT04336722), in patients with biliary atresia. BOLD, the largest prospective intervention trial ever conducted in biliary atresia, is a double-blind, randomized, placebo-controlled trial which will enroll approximately 200 patients at up to 75 sites globally to evaluate the efficacy and safety of odevixibat in children with biliary atresia who have undergone a Kasai procedure before age three months. The company also anticipates initiating a pivotal trial of odevixibat for Alagille syndrome by the end of 2020.
The odevixibat PFIC program, or elements of it, have received fast track, rare pediatric disease and orphan drug designations in the United States. In addition, the FDA has granted orphan drug designation to odevixibat for the treatment of Alagille syndrome, biliary atresia and primary biliary cholangitis. The EMA has granted odevixibat orphan designation, as well as access to the PRIority MEdicines (PRIME) scheme for the treatment of PFIC. Its Paediatric Committee has agreed to Albireo's odevixibat Pediatric Investigation Plan for PFIC. EMA has also granted orphan designation to odevixibat for the treatment of biliary atresia, Alagille syndrome and primary biliary cholangitis.