Global parcel delivery giant UPS Inc. has acquired the pharmaceutical logistics specialist Marken, continuing to expand its menu of specialty services for clinical trials and drug research in a growing array of countries.

Marken, based in Research Triangle Park, N.C., operates a global network of FDA-compliant, medical depots, and logistic hubs in 44 locations that support the storage and distribution of biological-sample shipments and clinical trial materials.

Terms of the acquisition were not disclosed, but UPS said the deal is expected to close by Dec. 31.

Atlanta-based UPS has been investing heavily in the specialized services it needs to claim a larger share of this lucrative market. In July, the company announced that it would expand its ability to provide temperature control, precision parcel tracking, and other capabilities for handling international shipments of drugs and biological specimens involved in clinical trials research.

Buying Marken will help UPS extend that network to a broader array of countries and strengthen its ability to guarantee temperature-controlled, 48-hour delivery of delicate medical samples such as frozen samples of blood, plasma, urine, and tissue, UPS said.

"The two companies are doing different things now, but they're complementary," said John Menna, UPS's vice president of strategy for healthcare logistics, in a phone interview. "Marken has a specialty in clinical trials logistics, and UPS has global capabilities in health care and life sciences in general. Together, we can offer a comprehensive solution end to end."

Marken plans to use the acquisition to leverage UPS' resources and continue to expand its web of clinical supply chain services as the pharmaceutical industry reaches out to an increasingly diverse array of countries.

"Finding patients for clinical trials around the world is becoming more difficult and more remote," Marken CEO Wes Wheeler said in an interview. "Drug developers are getting more and more narrow in how they define these patients, particularly around different types of cancer. So we are getting more patients in South America, Asia, and Eastern Europe."

To reach those scattered patients, Marken plans to add to its list of 10 depots, which are supply chain nodes where the company stores drug products and ancillary materials such as centrifuges, needles, syringes, drug leaflets, and laptops, he said. When a new patient is recruited for a drug trial, Marken employees create a tailored package and send it to one of the 45,000 clinics or hospitals where a doctor will administer drug doses and collect samples.

In addition, Marken will invest in its cloud-based inventory control software, called Solo, Wheeler said. The application tracks every dose of an experimental drug as it moves through the supply chain, ensuring that returned or unused drugs are destroyed, so the trial remains compliant with U.S. Food and Drug Administration (FDA) and European Medicines Agency (EMA) regulations.

Wheeler will continue to lead the Marken business after the acquisition, operating it as a wholly owned subsidiary of UPS.