Announcement • 3h
Astrazeneca plc Provides Update on Ultomiris Phase Iii Trial in Hsct-Tma
Astrazeneca PLC provided an update on the Phase III trial of Ultomiris in adults and adolescents with thrombotic microangiopathy after haematopoietic stem cell transplant. High-level results from the ALXN1210-TMA-313 Phase III clinical trial showed that Ultomiris (ravulizumab) did not achieve statistical significance for the primary endpoint of event-free survival through 26 weeks compared to placebo in adults and adolescents (aged 12 years or older) with thrombotic microangiopathy after haematopoietic stem cell transplant (HSCT-TMA). The primary endpoint was defined as the time from randomisation until TMA-related clinical worsening or death, whichever occurred first. In paediatric patients with HSCT-TMA, the ALXN1210-TMA-314 open-label Phase III trial of Ultomiris demonstrated clinically meaningful overall survival of 87.2% at 26 weeks and 73.4% at 52 weeks, as previously disclosed. Alexion, Astrazeneca Rare Disease is advancing regulatory filings for Ultomiris in paediatric patients with HSCT-TMA, based on these results and data from ALX-TMA-502, an external control study, which further supports clinically meaningful benefit on overall survival. Ultomiris showed a trend toward treatment benefit in adults and adolescents with HSCT-TMA at 26 weeks compared to placebo. Discussions with health authorities are ongoing regarding the interpretation of these data, including in the context of real-world evidence. Following HSCT, a procedure used with increasing frequency to treat some types of cancers and other diseases, the devastating and potentially life-threatening complication of TMA may occur. TMA can result in blood clots and damage to the walls of the smallest blood vessels in the circulatory system, which may lead to organ failure and death. HSCT-TMA is estimated to affect fewer than 6,000 people in the US. Haematopoietic stem cell transplant-associated thrombotic microangiopathy (HSCT-TMA) is a rare, severe and potentially life-threatening type of TMA that occurs following HSCT, a procedure used with increasing frequency to treat some types of cancers and other diseases. It is thought that factors associated with HSCT (i.e., conditioning regimens and other complications) induce overactivation and/or dysregulation of the complement system, driving HSCT-TMA. Symptoms of HSCT-TMA can overlap with those of other conditions, which can lead to a misdiagnosis and/or a significant delay in receiving an accurate diagnosis. HSCT-TMA can be fatal, with one-year survival rates in paediatric patients estimated between 17% and 44% and one-year overall survival rates ranging from approximately 17% to 58% in adults, based upon scientific literature. TMAs are a group of severe and potentially life-threatening rare disorders that cause blood clots and damage to the walls of the smallest blood vessels in the circulatory system. These blood clots can cause injury to organs that may lead to organ failure and death. Signs, symptoms and complications of TMA include organ damage (most commonly in the kidneys), low platelet count, red blood cell abnormalities [i.e. anaemia, fragmented red cells (schistocytes)], blood clots and high blood pressure. ALXN1210-TMA-313 is a global, Phase III, randomised, double-blind, placebo-controlled, multicentre trial evaluating the safety and efficacy of Ultomiris in adult and adolescent (aged 12 years or older) participants who have thrombotic microangiopathy (TMA) after haematopoietic stem cell transplant (HSCT). Participants were required to have received HSCT within the past 12 months at the time of screening, as well as a diagnosis of TMA that persisted for at least 72 hours after the initial management of any triggering condition or agent. The dosing regimen was confirmed in an open-label, single-arm period (Stage 1) based on data analysis after 14 participants had completed 21 days of treatment. Patients enrolled thereafter in the study were randomised 1:1 to receive either Ultomiris or placebo administered intravenously for a total of 26 weeks, in addition to best supportive care (Stage 2). Patients in the Stage 2 treatment arm received a loading dose of Ultomiris on Days 1, 5 and 10, followed by regular weight-based maintenance dosing of Ultomiris beginning on Day 15, every eight weeks through the treatment period. Upon completion of the treatment period, participants were followed for an additional 26 weeks. The primary endpoint is event-free survival during the 26-week treatment period, defined as the time from randomisation until clinical worsening or death. Key secondary endpoints include overall survival, non-relapse mortality and TMA response criteria. The trial enrolled 146 patients from 18 countries across North America, South America, Europe, Asia and Australia. ALXN1210-TMA-314 is a global, Phase III, open-label, single-arm, multicentre study evaluating the safety and efficacy of Ultomiris in paediatric patients (aged 28 days to less than 18 years of age) with thrombotic microangiopathy (TMA) after haematopoietic stem cell transplantation (HSCT). Participants were required to have received HSCT within the past 12 months at the time of screening, as well as a diagnosis of TMA that persisted for at least 72 hours after the initial management of any triggering condition or agent. The dosing regimen was confirmed based on data analysis after at least 10 participants had completed 21 days of treatment. All patients received a loading dose of Ultomiris on Days 1, 5 and 10, followed by regular weight-based maintenance dosing of Ultomiris beginning on Day 15 and administered every four weeks for patients weighing less than 20 kg or every eight weeks for patients weighing at least 20 kg through the 26-week treatment period, in addition to best supportive care. The administration of supplemental doses of Ultomiris between maintenance doses was guided by prespecified protocol requirements. The primary endpoint is complete TMA response (defined as a composite measure of haematologic and renal parameters) at 26 weeks. Secondary endpoints include overall survival, non-relapse mortality and TMA response criteria.