Bayer’s (BAYRY - Analyst Report) Healthcare unit and Johnson & Johnson’s (JNJ - Analyst Report) Janssen Pharmaceuticals recently collaborated with Portola Pharmaceuticals Inc. to evaluate the safety of PRT4445 in combination with blood thinner Xarelto (rivaroxaban).

The proof-of-concept study intends to evaluate the safety of PRT4445 in combination with Xarelto across multiple dosages to determine the dose of PRT4445 that will be able to reverse the anticoagulant activity of Xarelto in emergency situations. The study is expected to be completed by year-end.

Following the agreement, Portola will receive an undisclosed amount from Bayer and Johnson & Johnson. Bayer and Johnson & Johnson will provide development and regulatory guidance to Portola for the study. Portola retains all global development and commercialization rights for PRT4445.

We note that Xarelto, already approved for multiple indications, offers significant commercial potential. Xarelto is jointly developed by Bayer and the Janssen Research and Development unit of Johnson & Johnson. Johnson & Johnson is responsible for marketing the drug in the US, while Bayer is exclusively responsible for the marketing of the drug outside the US.

Xarelto was approved for the lucrative stroke prevention in nonvalvular atrial fibrillation (SPAF) indication in 2011. Xarelto is also approved for the treatment of pulmonary embolism (PE) and the prevention of recurrent deep vein thrombosis (DVT) and PE in adults. Bayer and Johnson & Johnson are looking to expand the drug’s label further.

Bayer carries a Zacks Rank #2 (Buy). Other large pharma stocks such as Eli Lilly and Company (LLY - Analyst Report) and Sanofi (SNY - Analyst Report) also carry a comparable rank.