March 24 (Reuters) - The U.S. Food and Drug Administration (FDA) on Friday approved Pharming Group's drug to treat a rare genetic disorder that leads to a weakened immune system, the Dutch company said. APDS causes a lack of functioning immune cells, B cells and T cells, which makes it difficult for people with this disorder to fight off bacterial and viral infections. At least two analysts expected the drug to be priced at as much as $400,000. Oppenheimer analyst Hartaj Singh expected Joenja to be priced between $250,000 and $400,000, and forecast peak sales of $200 million to $300 million, ahead of the approval. Joenja is an oral drug that targets and blocks a form of the protein called phosphoinositide 3-kinase delta (P13K).

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