US-based biopharmaceutical firm Insmed has completed patient enrolment in its randomised, placebo-controlled Phase II clinical trial of Arikace, or liposomal amikacin for inhalation, for treatment of adult patients with recalcitrant nontuberculous mycobacterial (NTM) lung disease in the US and Canada.
Patients who have been on the American Thoracic Society/Infectious Disease Society of America (ATS/IDSA) guideline therapy for at least six months before screening with persistently positive mycobacterial culture are eligible for taking part in the trial.
All patients continuing with their antibiotic regimen were given Arikace or placebo once daily using an optimised, investigational eFlow Nebulizer System (PARI Pharma GmbH).
According to the company, the primary efficacy endpoint in the trial is the semi-quantitative measurement of the change in mycobacterial density, a measurement used to evaluate the progress or decline in recalcitrant NTM patients, on a seven-point scale from baseline (day one) to the end of the randomised portion of the trial on day 84.
Time to sputum conversion, change in clinical signs and symptoms, change in patient related outcomes/quality of life and safety are some of the secondary, tertiary and exploratory endpoints fixed for the trial.
Patients are stratified for either Mycobacterium avium complex (MAC) infections or Mycobacterium abscessus infections and these pathogens account for about 85% in all patients with NTM lung disease in the US.
In addition, stratification is carried out based on patients with cystic fibrosis against those without the condition.
The company said that it has completed recruitment of 90 patients as required per protocol and the study is now sufficiently powered to achieve statistical significance with 80% power to demonstrate a one-step change in the seven-step scale measuring bacterial density.
After the randomised portion of the trial, all eligible patients can choose to receive Arikace once daily for an additional 84 days in an open-label design.
Insmed executive vice president of development and chief medical officer Renu Gupta said this is the first controlled clinical trial of an antibiotic in patients suffering from NTM lung disease.
"There are no FDA-approved treatments in this serious and increasingly prevalent infectious disease, and current treatment regimens include multiple antibiotics that must be given for prolonged periods of time, are often poorly tolerated and can be associated with severe toxicities," Gupta said.
The US Food and Drug Administration (FDA) has previously granted orphan drug, qualified infectious disease product (QIDP) and fast-track designations to Arikace for treatment of NTM lung infections.
The company has also started scientific advice working party (SAWP) process with the European Medicines Agency (EMA) for clarity on path forward for Arikace for NTM lung disease in Europe.
In addition, Insmed is currently assessing other international markets, such as Japan, where NTM lung infections are already a growing unmet medical need and is also developing a strategy to commercialise the drug in the globally uncontested orphan disease market.
Insmed president and chief executive officer Will Lewis said that the current tolerability challenges of the guideline therapy limit the practical utility of the ATS/IDSA recommended treatment regimen and are the reason why approximately half of diagnosed NTM patients do not receive or continue to take the recommended off label therapies.
"Pursuant to our QIDP status, we expect to continue our ongoing dialogue with the FDA regarding the regulatory pathway for registration and approval of ARIKACE to treat NTM," Lewis said.
"We remain on track to review and release the clinical data and related dialogue with the FDA by the end of the first quarter of 2014."
In a Phase III clinical trial of Arikace in cystic fibrosis patients, the company also showed that its liposomal inhalation technology safely and effectively delivers the drug to the site of infection and reduces bacterial burden.
Arikace is currently under development for the treatments of Pseudomonas lung infections in cystic fibrosis patients, lung infections due to non-tuberculous Mycobacteria and Pseudomonas lung infections in non-CF bronchiectasis patients and Pseudomonas Aeruginosa infections.
Image: ARIKACE is administered once daily using an optimised eFlow Nebulizer System (PARI Pharma GmbH). Photo: courtesy of Insmed.