Pharmosa Biopharm (Pharmosa) announced today (29th) that its licensing partner Liquidia held its first U.S. R&D Day in New York, presenting long-term results from the U.S. Phase III open-label trial of L606 for the treatment of pulmonary arterial hypertension (PAH). The trial showed strong efficacy, outperforming current therapies. According to the licensing agreement, Liquidia will immediately initiate the global Phase III Re-Spire PH-ILD trial, targeting both first-class PAH and third-class pulmonary hypertension with interstitial lung disease (PH-ILD) indications, addressing a market exceeding NT$100 billion.
The U.S. Phase III trial of L606 for PAH followed 28 patients for 48 weeks. Safety and tolerability data showed most patients could safely and successfully switch from existing therapies Tyvaso or Tyvaso DPI to L606. Co-administration with other PAH drugs was well tolerated, with no significant safety concerns observed. Notably, L606 greatly reduced the cough commonly associated with inhaled therapies—only 14.3% of participants reported mild coughing, far below the rates reported in Tyvaso and Tyvaso DPI (54% and 35% per FDA labels), demonstrating a significant reduction in this disruptive side effect.
Regarding efficacy, patients who switched from Tyvaso or Tyvaso DPI to L606 (Trial Group A) showed stable or significant improvement after treatment. The primary endpoint—6-minute walk distance (6MWD)—increased by an average or median of 29.4 meters and 22.5 meters, respectively. Patients naïve to prostacyclin therapy (Trial Group B) showed 6MWD improvements of 72.3 meters (mean) and 22.5 meters (median) after L606 treatment.
The trial further demonstrated that L606 requires only twice-daily inhalation to achieve 24-hour therapeutic coverage. After 48 weeks of treatment, the median 6MWD measured before the first daily inhalation increased by 24.3 meters from baseline, closely matching post-inhalation median values (22.5 meters), confirming stable, long-lasting drug concentrations with both rapid onset and sustained control.
Remarkably, among PH-ILD patients (all switched from Tyvaso or Tyvaso DPI), although enrollment numbers were smaller, 75% of patients experienced a median or mean 6MWD increase of over 60 meters after switching to L606. These results highlight L606’s potential not only for PAH but also for the clinically more challenging PH-ILD population, demonstrating clear clinical breakthroughs and long-term value.
Based on these findings, Liquidia will, under the agreement, immediately launch the global Re-Spire Phase III PH-ILD trial, marking a new stage in development. This trial will simultaneously target PAH and PH-ILD indications, addressing a global market exceeding NT$100 billion.
Pharmosa Biopharm General Manager Pei Gan stated that the Phase III results confirm L606’s superior safety and efficacy compared to current therapies, providing PAH and PH-ILD patients with stable or continuously improved outcomes and demonstrating long-term therapeutic potential.
Liquidia has completed trial design discussions with the U.S. FDA and the European EMA for the Re-Spire study and received approval to use a single pivotal Re-Spire trial for new drug applications (NDA/MAA). Pharmosa will assist Liquidia in accelerating global clinical trials and advancing regulatory approvals in their respective regions, aiming to bring this innovative therapy to market as soon as possible.
Resource: 國邑*L606美國三期長期數據報捷，PH-ILD全球三期臨床將展開
