Narrative review to capture patients' perceptions and opinions about non-response and response to biological therapy for severe asthma.

BACKGROUND: There are now many biological therapies to treat severe asthma. To assess which work best for which patient, we need to develop definitions of response. This narrative review aims to capture severe asthma patients' perceptions about non-response and response to biological therapy. METHODS: Four bibliographic databases were searched from inception to September 2021. Grey literature was searched with the involvement of patient representatives. A thematic approach was used for synthesis. No qualitative studies specifically explore patients' perspectives on response to biological therapy for severe asthma. Three papers and one published asthma patient interview were included. Relevant grey literature was included from online discussion forums, blogs and social media websites. RESULTS: Adult patients framed positive response to biological therapy in terms of reduced burden of disease and treatment. Both were multifaceted. Some patients experienced reduced benefit from biological therapy over time. There was a group of patients who described a limited response or non-response to biological therapy. This was framed within the context of continuing hospitalisation and oral corticosteroid treatment. The speed of onset of benefit was felt to be important by some. CONCLUSIONS: Definitions of non-response and response need to be patient-centred, yet there is a complete lack of qualitative research focused on this topic. By combining relevant published and grey literature we have provided a description of adult patients' perceptions of response to biological therapy in severe asthma. We now need to understand the views of children and adolescents with severe asthma and their carers, and diverse patient experiences in real-world settings.

Identifying and appraising outcome measures for severe asthma: a systematic review.

BACKGROUND: Valid outcome measures are imperative to evaluate treatment response, yet the suitability of existing end-points for severe asthma is unclear. This review aimed to identify outcome measures for severe asthma and appraise the quality of their measurement properties. METHODS: A literature search was performed to identify "candidate" outcome measures published between 2018 and 2020. A modified Delphi exercise was conducted to select "key" outcome measures within healthcare professional, patient, pharmaceutical and regulatory stakeholder groups. Initial validation studies for "key" measures were rated against modified quality criteria from COnsensus-based Standards for the selection of health Measurement INstruments (COSMIN). The evidence was discussed at multi-stakeholder meetings to ratify "priority" outcome measures. Subsequently, four bibliographic databases were searched from inception to 20 July 2020 to identify development and validation studies for these end-points. Two reviewers screened records, extracted data, assessed their methodological quality and graded the evidence according to COSMIN. RESULTS: 96 outcome measures were identified as "candidates", 55 as "key" and 24 as "priority" for severe asthma, including clinical, healthcare utilisation, quality of life, asthma control and composite. 32 studies reported measurement properties of 17 "priority" end-points from the latter three domains. Only the Severe Asthma Questionnaire and Childhood Asthma Control Test were developed with input from severe asthma patients. The certainty of evidence was "low" to "very low" for most "priority" end-points across all measurement properties and none fulfilled all quality standards. CONCLUSIONS: Only two outcome measures had robust developmental data for severe asthma. This review informed development of core outcome measures sets for severe asthma.