Tilray shares were up US$11.43 at US$41.52 in late-morning trading on the Nasdaq market.
Grow Pharma is a leading medical cannabis distributor in the United Kingdom.
Tilray, based in Nanaimo, B.C., says it expects to have a range of medical cannabis products available for patients in the United Kingdom by March.
Tilray announced a deal last year to merge with Leamington, Ont.-based Aphria Inc.
The cannabis companies have said the move will help them slash costs and give them control of the biggest slice of the Canadian retail market.
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