Positive data from BioMarin's MOR-100 Phase 1/2 extension study on Morquio syndrome

BioMarin Pharmaceutical Inc. (Nasdaq: BMRN) today announced an update on the GALNS Phase 1/2 extension study (MOR-100) in which patients have continued treatment on an ongoing basis.  

Patients originally enrolled in the initial Phase 1/2 study of GALNS (MOR-002) were continued on therapy in a new extension study (MOR-100).  In the MOR-100 study, patients were treated at a 2.0 mg/kg/week dose and have been followed for an additional 24 weeks.  Previously, these patients were dosed at 0.1 mg/kg/week, 1.0 mg/kg/week and 2.0 mg/kg/week for 12 weeks each in the Phase 1/2 study (MOR-002).  Following the dose escalation phase, patients were then dosed at 1.0 mg/kg/week for an additional 36 to 48 weeks as part of the MOR-002 extension, before continuing on to MOR-100.  Taken together, these patients have received GALNS for approximately two years.

"We now have data from MPS IVA patients that have been on GALNS for approximately 2 years and the data continues to look promising," said Hank Fuchs, M.D., Chief Medical Officer of BioMarin.  "Looking at the Phase 1/2 data in totality, we now see that the endurance and pulmonary function improvements are durable and clinically meaningful compared to baseline, and similar in magnitude to what we have observed during the development of Naglazyme and Aldurazyme.  These data are encouraging in regard to the ongoing Phase 3 study in that the benefits of GALNS appear consistently sustained, and no new risks have emerged.  Enrollment in the Phase 3 study is accelerating and its execution is BioMarin's highest product development priority."

Preliminary highlights, including information on patients treated for 24 additional weeks at 2.0 mg/kg/week are provided below.  Data from the extension study will be submitted for presentation at the World Lysosomal Storage Disease conference in February 2012.  

Highlights of MOR-100 Extension Study:

• No new or consistent patterns of clinically meaningful or treatment limiting adverse events were reported.  
• Measures of 6-minute walk distance, 3-minute stair climb and pulmonary function all generally improved and were sustained for at least 2 years.
• For the group of patients with baseline 6-minute walk distance <325 meters, mean walk distance remains consistently improved for the entire period of observation.  Specifically, 24 weeks after resuming 2.0 mg/kg/week dosing in MOR-100, the mean 6-minute walk distance was 38 meters.  This is roughly equivalent to that observed after the first 24 weeks of the original Phase 1/2 trial (MOR-002).  The ongoing Phase 3 study is using mean improvement in 6-minute walk distance in patients with baseline walk distance <325 meters as the primary endpoint.  
• 6-minute walk distance improvements were greater in the subgroup of patients with baseline walk distance <325 meters.  However, variability of this test increases with longer-term follow-up, likely as a result of issues related to the progressive nature of Morquio syndrome. Several measures to reduce variability have already been incorporated in the ongoing Phase 3 trial: large sample size, selection of patients not expected to require surgical correction of skeletal deformity in the subsequent 24 weeks, duplicate measures of 6-minute walk test, conclusion of the trial at 24 weeks, extensive oversight of the performance of the walk test according to ATS criteria and inclusion of placebo for comparative purposes.
• 3-minute stair climb and pulmonary function have consistently improved over the entire duration of the study.  24 weeks after returning to 2.0 mg/kg, patients can now climb a mean of 13.6 stairs per minute and FVC has improved a mean of 15.9%, compared to 6.9 stairs per minute and 1.5% reported at the end of the first 24 weeks of the Phase 1/2 trial.  Stair climb and pulmonary function are secondary and tertiary endpoints, respectively, in the ongoing prospective Phase 3 trial.
• The data from the extension study to date support 6-minute walk distance as the primary endpoint and patients with baseline walk distance <325 meters as an entry criteria in the ongoing GALNS Phase 3 trial, given the large and durable effect of the drug on these measures in this population.

Simon Jones, Consultant in Paediatric Metabolic Medicine, St. Mary's Hospital, Manchester UK commented, "I'm pleased with the outcome of the GALNS program to date.  The longer-term data look good with sustained improvements in endurance and pulmonary function.  Patients feel stronger and function better than I expected.  All in all, we look forward to the results of the Phase 3 study as it is well designed and will, if successful, support introduction of an important product to patients in need."

Hank Fuchs, M.D., Chief Medical Officer of BioMarin added, "It's remarkable that improvements in endurance are sustained in spite of the severe and progressive nature of Morquio syndrome.  Patients with Morquio syndrome can miss therapy, for example, due to the need for corrective surgery.  In spite of that, resumption of therapy returns patients to their original state of health or better."