Sandy Springs-based UPS is acquiring medical shipper Marken in a move to boost its position in the healthcare logistics and supply chain industry.

Marken, which is based at the Research Triangle Park in Durham, N.C., specializes in logistics for clinical trials. It is privately-held and has 44 locations around the world and more than 650 employees who manage drug and biological shipments.

The companies did not disclose terms of the deal, which is expected to close by the end of the year subject to regulatory approvals.

Marken CEO Wes Wheeler will continue to lead the Marken business, which will be a wholly-owned subsidiary of UPS.

The Marken deal is part of a string of UPS investments and acquisitions in clinical trial logistics for drug and vaccine research. The shipments of biological samples from clinical trial sites to central laboratories require specialized handling, since they are urgent and often need to be kept at specific temperatures.