Open-Label Rollover Study of PBI 4050 in Subjects With Alström Syndrome

Inclusion Criteria: * Subject completed a preceding ProMetic-sponsored Alström syndrome study with PBI-4050. * Subject has signed informed consent * Subject has a documented diagnosis of Alström syndrome * Subject receiving antidiabetic medications is able and willing to self-monitor blood glucose levels * Subject must be willing to forego other forms of experimental drug treatment during the study. * Female subjects of childbearing potential must have a negative serum pregnancy test at screening and agree to use adequate birth control from screening throughout the study and for 30 days after the last Investigational Medicinal Product (IMP) administration * If a male subject has not been vasectomized at least 6 months before screening and partners with a woman of childbearing potential, he must be willing to use an acceptable contraceptive method throughout the study and for 30 days after the last IMP administration. Exclusion Criteria: * Subject discontinued PBI-4050 for safety reasons from any preceding ProMetic-sponsored Alström syndrome study with PBI-4050 * Subject has had a documented episode of severe hypoglycaemia within 12 months before screening and investigator judges that the subject is unable to adequately monitor their glucose levels. * Subject has uncontrolled hypertension with BP \> 170/100 mmHg as determined at screening. * Woman who is pregnant, breast-feeding, or planning a pregnancy during the course of the study as determined at screening * Subject has any condition that, in the investigator's opinion, is likely to interfere with study conduct and compliance * Subject has a history of an allergic reaction to PBI-4050 or any of its excipients.