Definitions of non-response and response to biological therapy for severe asthma: a systematic review.

Background: Biologics have proven efficacy for patients with severe asthma but there is lack of consensus on defining response. We systematically reviewed and appraised methodologically developed, defined and evaluated definitions of non-response and response to biologics for severe asthma.
Methods: We searched four bibliographic databases from inception to 15 March 2021 . Two reviewers screened references, extracted data, and assessed methodological quality of development, measurement properties of outcome measures and definitions of response based on COnsensus-based Standards for the selection of health Measurement INstruments (COSMIN). A modified GRADE (Grading of Recommendations Assessment, Development and Evaluation) approach and narrative synthesis were undertaken.
Results: 13 studies reported three composite outcome measures, three asthma symptoms measures, one asthma control measure and one quality of life measure. Only four measures were developed with patient input; none were composite measures. Studies utilised 17 definitions of response: 10 out of 17 (58.8%) were based on minimal clinically important difference (MCID) or minimal important difference (MID) and 16 out of 17 (94.1%) had high-quality evidence. Results were limited by poor methodology for the development process and incomplete reporting of psychometric properties. Most measures rated "very low" to "low" for quality of measurement properties and none met all quality standards.
Conclusions: This is the first review to synthesise evidence about definitions of response to biologics for severe asthma. While high-quality definitions are available, most are MCIDs or MIDs, which may be insufficient to justify continuation of biologics in terms of cost-effectiveness. There remains an unmet need for universally accepted, patient-centred, composite definitions to aid clinical decision making and comparability of responses to biologics.
Competing Interests: Conflict of interests: E. Khaleva and A. Rattu declare funding for the present manuscript from the 3TR European Union Innovative Medicines Initiative 2 paid to the university. C. Brightling declares grants from GlaxoSmithKline, AstraZeneca, Novartis, Chiesi, Boehringer Ingelheim, Genentech, Roche, Sanofi, Mologic and 4DPharma, consulting fees from GlaxoSmithKline, AstraZeneca, Novartis, Chiesi, Boehringer Ingelheim, Genentech, Roche, Sanofi, Mologic, 4DPharma and Teva, and support from the 3TR project. A. Bourdin reports being an investigator for clinical trials promoted by AstraZeneca, Chieisi, GlaxoSmithKline, Boehringer Ingelheim, Novartis, Regeneron and Sanofi; having received fees for lectures, attendance of meeting and consultancy from AstraZeneca, Chieisi, GlaxoSmithKline, Boehringer Ingelheim, Novartis, Regeneron and Sanofi; having received research grants from AstraZeneca and Boehringer Ingelheim; and participation on a data safety monitoring or advisory board of AB Science. A. Bossios has received lecture fees from GlaxoSmithKline, AstraZeneca, Teva and Novartis; honoraria for advisory board meetings from GlaxoSmithKline, AstraZeneca, Teva, Novartis and Sanofi; and received support for attending meetings from AstraZeneca and Novartis, all outside the present work; reports being a member of the Steering Committee of SHARP, Secretary of Assembly 5 (Airway Diseases, Asthma, COPD and Chronic Cough) of the European Respiratory Society and Vice-chair of the Nordic Severe Asthma Network (NSAN). K.F. Chung has received honoraria for participating in advisory board meetings of GlaxoSmithKline, AstraZeneca, Roche, Novartis, Merck and Shionogi regarding treatments for asthma, COPD and chronic cough, and has also been renumerated for speaking engagements for Novartis and AstraZeneca. R. Chaudhuri has received lecture fees from GlaxoSmithKline, AstraZeneca, Teva, Chiesi, Sanofi and Novartis; honoraria for advisory board meetings from GlaxoSmithKline, AstraZeneca, Teva, Chiesi and Novartis; sponsorship to attend international scientific meetings from Chiesi, Napp, Sanofi, Boehringer, GlaxoSmithKline and AstraZeneca, and a research grant to her Institute from AstraZeneca for a UK multicentre study. C. Coleman declares funding received to support this work by the European Lung Foundation (ELF) from the European Commission's Innovative Medicines Initiative 2 Joint Undertaking (JU) under grant agreement number 831434 (3TR), and is an employee of the ELF. R. Djukanovic declares funding from European Respiratory Society, Teva, GlaxoSmithKline, Novartis, Sanofi and Chiesi for the SHARP CRC, consulting fees for Synairgen; honorarium for a lecture from GlaxoSmithKline, participation on a data safety monitoring board or advisory board for Kymab (Cambridge) and shares in Synairgen, outside the submitted work. S-E. Dahlen declares funding from 3TR IMI Grant; consulting fees from AstraZeneca, Cayman Co., GlaxoSmithKline, Novartis, Regeneron, Sanofi and Teva; honoraria for lectures from AstraZeneca and Sanofi. A. Exley declares being a minority shareholder in GlaxoSmithKline PLC. L. Fleming declares participation in advisory boards and honoraria for lectures from Sanofi, Respiri UK, AstraZeneca, Novartis and Teva, outside the scope of this publication. All payments were made to her institution. A. Gupta received speaker and advisory board fees from GlaxoSmithKline, Novartis, AstraZeneca and Boehringer Ingelheim. A. Gupta's institution had received research grants from GlaxoSmithKline, Novartis, AstraZeneca and Boehringer Ingelheim. E. Hamelmann declares support from the German Ministry of Education and Research (BMBF) and German Asthma Net (GAN) e.V.; funding for research in severe asthma in children (CHAMP-01GL1742D) and for Severe Asthma Register. G.H. Koppelman reports receiving research grants from the Lung Foundation of the Netherlands, Ubbo Emmius Foundation, H2020 European Union, Teva, GlaxoSmithKline and Vertex, outside this work (money to institution); he reports memberships of advisory boards to GlaxoSmithKline and PURE-IMS, outside this work (money to institution). E. Melen has received consulting fees from AstraZeneca, Chiesi, Novartis and Sanofi outside the submitted work. V. Mahler has no conflict of interest but declares that the views expressed in this review are the personal views of the author and may not be understood or quoted as being made on behalf of or reflecting the position of the respective national competent authority, the European Medicines Agency, or one of its committees or working parties. F. Singer reports being an investigator for clinical trials promoted by Vertex and having received fees for lectures from Vertex and Novartis, outside the submitted work. C. Porsbjerg declares grants, consulting fees and honoraria from AstraZeneca, GlaxoSmithKline, Novartis, Teva, Sanofi, Chiesi and ALK (paid to institution and personal honoraria); participation in the advisory board for AstraZeneca, Novartis, Teva, Sanofi and ALK, outside the submitted work. V. Ramiconi reports grants paid to EFA from Pfizer, Novartis, AstraZeneca, Sanofi, Chiesi Farmaceutici, Regeneron, DBV Technologies, MSD, GlaxoSmithKline, Aimmune, LeoPharma, AbbVie, Boehringer Ingelheim, OM Pharma and Roche; payment for expert testimony from Novartis Global Respiratory Patient Council 2021 and Novartis EPIS Steering Committee to EFA. G. Roberts declares EU IMI funding and consulting fees from AstraZeneca paid to his institution. No other author has any conflict of interest to declare.
(Copyright ©The authors 2023.)