Geron (GERN) was down more than 66% in Thursday’s pre-market session as Johnson & Johnson’s (JNJ) Janssen Biotech unit terminated the companies’ 2014 collaboration and license agreement.

Janssen made this decision as the result of a strategic portfolio evaluation and prioritization of assets, Geron said.

Geron has regained the global rights to develop and commercialize imetelstat, a drug being developed for the treatment of hematologic myeloid malignancies.

Janssen has no further obligations to fund any of the imetelstat clinical trials, Geron said. Transition of the imetelstat program to Geron is expected to occur over 12 months with operational support from Janssen.

Geron also revised its 2018 operating expenses guidance to approximately $37 million from $30 million.

Janssen is expected to supply imetelstat to Geron for up to 24 months during a transition period for clinical manufacturing.