Nov 15 (Reuters) - An experimental drug to treat a rare genetic disorder that causes skeletal malformation and a host of related lung, eye ear and heart problems confers "modest" benefit, according to an initial review by the U.S. Food and Drug Administration.

The drug, Vimizim, is being developed by BioMarin Pharmaceutical Inc to treat Morquio A Syndrome, one of a group of lysosomal storage disorders known as mucopolysaccharidoses (MPS). Morquio A Syndrome is also known as MPS IV-A.

The FDA's review was posted on the agency's website on Thursday ahead of a meeting of outside advisers to the agency scheduled to take place on Nov. 19. The FDA is not bound to follow the advice of its advisory panels but typically does so.

The FDA's reviewers said the main safety concerns relate to anaphylaxis and allergic reactions. They also said further studies may be needed to better understand the role of antibody development on long-term efficacy and safety.