From DREAM to REALITI-A and beyond: Mepolizumab for the treatment of eosinophil-driven diseases.

Effective treatment of inflammatory diseases is often challenging owing to their heterogeneous pathophysiology. Understanding of the underlying disease mechanisms is improving and it is now clear that eosinophils play a complex pathophysiological role in a broad range of type 2 inflammatory diseases. Standard of care for these conditions often still includes oral corticosteroids (OCS) and/or cytotoxic immune therapies, which are associated with debilitating side effects. Selective, biological eosinophil-reducing agents provide treatment options that improve clinical symptoms associated with eosinophilic inflammation and reduce OCS use. Mepolizumab is a humanized monoclonal antibody that binds to and neutralizes interleukin-5, the major cytokine involved in eosinophil proliferation, activation, and survival. Mepolizumab is approved for the treatment of severe eosinophilic asthma, eosinophilic granulomatosis with polyangiitis and hypereosinophilic syndrome. Additionally, the efficacy of add-on mepolizumab has been observed in patients with severe chronic rhinosinusitis with nasal polyposis and chronic obstructive pulmonary disease with an eosinophilic phenotype. Here, we review the development, approval, and real-world effectiveness of mepolizumab for the treatment of patients with severe eosinophilic asthma, from the DREAM to REALITI-A studies, and describe how knowledge from this journey extended to the use of mepolizumab and other biologics across a broad spectrum of eosinophilic diseases.

Strategies for composite estimands in confirmatory clinical trials: Examples from trials in nasal polyps and steroid reduction.

The draft addendum to the ICH E9 regulatory guideline asks for explicit definition of the treatment effect to be estimated in clinical trials. The draft guideline also introduces the concept of intercurrent events to describe events that occur post-randomisation that may affect efficacy assessment. Composite estimands allow incorporation of intercurrent events in the definition of the endpoint. A common example of an intercurrent event is discontinuation of randomised treatment and use of a composite strategy would assess treatment effect based on a variable that combines the outcome variable of interest with discontinuation of randomised treatment. Use of a composite estimand may avoid the need for imputation which would be required by a treatment policy estimand. The draft guideline gives the example of a binary approach for specifying a composite estimand. When the variable is measured on a non-binary scale, other options are available where the intercurrent event is given an extreme unfavourable value, for example comparison of median values or analysis based on categories of response. This paper reviews approaches to deriving a composite estimand and contrasts the use of this estimand to the treatment policy estimand. The benefits of using each strategy are discussed and examples of the use of the different approaches are given for a clinical trial in nasal polyposis and a steroid reduction trial in severe asthma.

Lamivudine for patients with chronic hepatitis B and advanced liver disease.

BACKGROUND: The effectiveness of antiviral therapy in preventing disease progression in patients with chronic hepatitis B and advanced fibrosis or cirrhosis is unknown. METHODS: Patients with chronic hepatitis B who had histologically confirmed cirrhosis or advanced fibrosis were randomly assigned in a 2:1 ratio to receive lamivudine (100 mg per day) or placebo for a maximum of five years. Of 651 patients, 436 were assigned to receive lamivudine and 215 to receive placebo. The primary end point was time to disease progression, defined by hepatic decompensation, hepatocellular carcinoma, spontaneous bacterial peritonitis, bleeding gastroesophageal varices, or death related to liver disease. An independent data and safety monitoring board monitored the progress of the study and performed interim analyses of the data. RESULTS: We randomly assigned 651 patients (98 percent Asian and 85 percent male) to receive lamivudine or placebo. The study was terminated after a median duration of treatment of 32.4 months (range, 0 to 42) owing to a significant difference between treatment groups in the number of end points reached. End points were reached by 7.8 percent of the patients receiving lamivudine and 17.7 percent of those receiving placebo (hazard ratio for disease progression, 0.45; P=0.001). The Child-Pugh score increased in 3.4 percent of the patients receiving lamivudine and 8.8 percent of those receiving placebo (hazard ratio, 0.45; P=0.02), whereas hepatocellular carcinoma occurred in 3.9 percent of those in the lamivudine group and 7.4 percent of those in the placebo group (hazard ratio, 0.49; P=0.047). Genotypic resistance YMDD mutations developed in 49 percent of the patients treated with lamivudine, and the Child-Pugh score was more likely to increase in patients with these mutations than in the other patients treated with lamivudine (7 percent vs. <1 percent). Overall, 12 percent of the patients in the lamivudine group and 18 percent of the patients in the placebo group reported serious adverse events. CONCLUSIONS: Continuous treatment with lamivudine delays clinical progression in patients with chronic hepatitis B and advanced fibrosis or cirrhosis by significantly reducing the incidence of hepatic decompensation and the risk of hepatocellular carcinoma.