Swiss biotech Idorsia spun out of Actelion before it was taken over by Johnson & Johnson earlier this year, but the big pharma has confirmed it will still play a big part in one of its lead products.

J&J’s Janssen Biotech unit just exercised a $230 million option to partner with Idorsia on aprocitentan (ACT-132577), a drug for resistant hypertension that hit its objectives in a phase 2 test earlier this year and is due to start registration trials early next year.

Idorsia gets $160 million of the fee right away, with the remainder booked as contract revenue over the next three years—adding to its healthy cash position, which was $1 billion at the time it separated from Actelion in June. J&J’s $30 billion takeover deal with Actelion included options on four of Idorsia’s pipeline drugs—all of which were in phase 2—and gave the brand-new biotech a line on a deep-pocketed partner from the off.

Idorsia is headed by Actelion founder Jean-Paul Clozel, who consented to the takeover deal with J&J only after the two parties agreed to hive off certain R&D projects into the spinoff company.

The two companies now say they intend to split phase 3 development trials for aprocitentan in resistant hypertension, with Janssen selling the drug if it reaches the market and paying Idorsia 20% to 35% royalties depending on sales levels.

Janssen’s decision to come on board follows a review of the recent trial data, which showed statistically significant reductions in mean diastolic and systolic blood pressure in patients with resistant hypertension, as well as an end-of-phase 2 meeting with the FDA.

Aprocitentan is a dual endothelin receptor antagonist that draws on Actelion’s three decades of experience in this drug class, which has yielded big-selling products such as pulmonary arterial hypertension therapy Tracleer (bosentan)—now off-patent—and follow-up Opsumit (macitentan).

The new drug is a metabolite of macitentan and is being developed for patients whose high blood pressure is uncontrolled despite the use of at least three antihypertensive drugs, a group which is at a much higher risk of cardiovascular disease.

According to Indorsia’s chief scientific officer, Martine Clozel, there could also be scope for the drug beyond resistant hypertension. "Aprocitentan can be envisioned to have many other potential applications [which] makes the collaboration with Janssen even more meaningful for us," she remarked.

Shares in Idorsia spiked on news of the licensing deal but fell back quickly. The stock is still trading at more than twice its CHF 10 (around $10) debut price, currently knocking on the door of CHF 22.