^Allschwil, Switzerland - November 3, 2023

Idorsia Ltd (SIX: IDIA) announced today that further data for aprocitentan,

Idorsia's investigational dual endothelin receptor antagonist for the treatment

of patients with resistant hypertension, were presented as an oral presentation

entitled "Effects of aprocitentan on blood pressure lowering and proteinuria in

patients with chronic kidney disease and resistant hypertension

(https://www.asn-online.org/education/kidneyweek/2023/program-

abstract.aspx?controlId=3944397)" by George Bakris, MD, at the American Society

of Nephrology (ASN) Kidney Week 2023.

Patients with hypertension can often successfully control their blood pressure

by combining a healthier lifestyle with effective medication. However,

approximately 10% of patients have resistant hypertension where the blood

pressure remains high despite receiving at least three antihypertensive

medications of different pharmacological classes, including a diuretic, at

optimal doses.

The Phase 3 PRECISION study demonstrated both the safety and the efficacy of

aprocitentan to significantly lower blood pressure (BP) in patients with

resistant hypertension on top of at least three antihypertensive medications of

different classes, including a diuretic. Detailed results were published in The

Lancet and presented as a Late-Breaking Science presentation during the American

Heart Association (AHA) Scientific Sessions in November 2022. More details and

commentary can be found in the dedicated press release

(https://www.idorsia.com/investors/news-and-events/media-release-

details?newsId=2869821) and an investor webcast

(https://www.idorsia.com/investors/news-and-events/Apro-session-AHA-

2022) featuring Prof. Markus Schlaich, an investigator in PRECISION.

The presentation at ASN Kidney Week 2023 focused on the effect of aprocitentan

on BP in a subgroup of 162 patients with stage 3 or 4 chronic kidney disease

(CKD), defined by an estimated glomerular filtration rate (eGFR) of 15 to

°