Shares of MannKind Corp. jumped nearly 90 percent Tuesday after the Westlake Village biotech announced an agreement with United Therapeutics Corp. to develop an inhalable drug to treat a form of hypertension. United Therapeutics will pay MannKind $45 million upfront and up to an additional $50 million if the company hits certain targets to develop a dry powder form of the drug treprostinil. Maryland-based United Therapeutics has exclusive rights to license the drug and will be responsible for global development, regulatory and commercial activities. The firm also has the option to license other hypertension treatments with Mannkind’s inhalable drug delivery system. In addition, the two companies entered into a joint research agreement for which MannKind will receive a $10 million payment. The much-needed cash infusion comes after MannKind made several equity swaps this year to restructure its debt to creditors. Last month, the company reported a quarterly loss of $22.7 million; as of June 30, the company had cash and cash equivalents of $26.7 million. Shares of MannKind (MNKD) rose 98 cents, or 89 percent, on Tuesday to close at $2.08 on the Nasdaq.