Mind Medicine Inc., a psychedelics-based medicine startup backed by Shark Tank’s Kevin O’Leary, closed a $24.2 million funding round ahead of plans to go public next week.

It is the first among a new crop of companies pursuing psychedelics-based therapies to go public, in a test of investors’ appetite to back drugs that have shown promise in treating mental-health ailments but remain illegal in many countries including the U.S.

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