Harmony Biosciences announced Monday that it agreed to acquire Zynerba Pharmaceuticals for up to $200 million, gaining a potential treatment for symptoms of fragile X syndrome and other rare neuropsychiatric disorders. Zynerba's lead asset is Zygel (cannabidiol), also known as ZYN002, a non-euphoric cannabinoid permeation-enhanced gel designed for transdermal delivery through the skin and into the circulatory system.According to the companies, the therapy is manufactured through a synthetic process and is not extracted from the cannabis plant, so it is devoid of tetrahydrocannabinol (THC) – the main psychoactive component of cannabis – thus potentially allowing it to become a non-scheduled product, if approved."In addition to the strength of our core business in narcolepsy and our current life-cycle management programmes, led by idiopathic hypersomnia, we are excited to continue to diversify our portfolio beyond sleep/wake by adding Zynerba's clinical development programmes to our pipeline," said Harmony CEO Jeffrey Dayno.Under the terms of the buyout, Harmony will begin a tender offer to acquire all outstanding shares of Zynerba for close to $1.11 per share in cash, or $60 million. The deal also includes one contingent value right (CVR) per share, giving holders the right to receive potential additional payments of up to $140 million, or about $2.54 a share, tied to clinical, regulatory and commercial milestones related to Zygel.Previous clinical setback"With Harmony's scale [and] resources…they are well positioned to potentially bring to market the first pharmaceutical product indicated for the treatment of behavioural symptoms of fragile X syndrome," commented Zynerba chief executive Armando Anido. The transaction is expected to close by the fourth quarter.In 2017, Zynerba reported that a Phase II study of Zygel in adult epilepsy patients with focal seizures had failed to meet its primary endpoint. The company later said that another candidate, dubbed ZYN001, a pro-drug of THC delivered via a transdermal patch, did not achieve target blood levels of THC in healthy volunteers.