Merck KGaA subsidiary Merck Serono has amended its development and license deal with Opexa Therapeutics for Tcelna, handing over $3 million to further support an ongoing trial with the personalised immunotherapy for multiple sclerosis.

The German drugmaker’s payment will help fund the current Phase IIb clinical study assessing Tcelna (imilecleucel-T) for patients with secondary progressive MS, as well as support planning of potential late-stage trials.

Under their original 2013 deal, Merck Serono paid Opexa a $5 million upfront fee for the option to exclusively license Tcelna (imilecleucel-T) - a potential first-in-class personalised therapy which has received US fast-track designation - for the treatment of MS. 

Merck’s option can be exercised prior to or upon completion of the ongoing mid-stage study, top-line data from which is expected in the second half of 2016. If this occurs, Merck will pay Opexa another $25 million (or $15 million, depending upon whether certain conditions are met) for worldwide development and commercial rights excluding Japan, and fund its further development.