Summary
What is this summary about?
This is a plain language summary of an article published in The Lancet Neurology in 2024. The article describes the results of the ADHERE clinical study, which involved people with chronic inflammatory demyelinating polyradiculoneuropathy, or CIDP for short. CIDP is a rare autoimmune disease that affects nerves in the arms and legs. There is a need for new treatment options for CIDP that reduce symptoms, are convenient to take, and have manageable side effects.
What happened in this study?
In this study, researchers looked at how well efgartigimod worked in people with CIDP and the side effects people had during the study. Stage A of the study aimed to find people who had signs of reduced symptoms and disability after receiving efgartigimod. People received weekly injections of efgartigimod under the skin (subcutaneous). Stage B compared efgartigimod with a placebo treatment to find out how well efgartigimod worked and the side effects that people had.
What were the results?
Overall, 66% of all participants in ADHERE showed signs of clinical improvement after receiving efgartigimod. Half of these people had first signs of clinical improvement in about 22 days. Compared to a placebo, people who received efgartigimod had a reduced risk of CIDP symptoms getting worse or returning (relapsing). More people who received efgartigimod were able to carry out their daily activities and maintained grip strength than those who took a placebo. Most side effects that people developed during the study were mild or moderate.
What do the results mean?
In this study, people who received efgartigimod had stable or improving symptoms for up to 48 weeks, while more people who received a placebo had worsening strength, disability, and quality of life. Subcutaneous injections of efgartigimod may offer a more convenient option for people with CIDP compared with current treatments.
Keywords: chronic inflammatory demyelinating polyradiculoneuropathy, efgartigimod, health-related quality of life, immunoglobulin Fc fragment, plain language summary of publication, randomized clinical trial
Acknowledgments
We thank the participants, caregivers, participant advocates, clinicians, and support staff who have collaborated on the design and execution of this trial; support staff can be found on the original article (appendix pp 8–12). We also thank Halozyme Therapeutics for their partnership and providing their proprietary technology for the treatment. Writing support for this plain language summary of publication was provided by Macarena Ramos Gonzalez and Jacqui Oliver from Envision Pharma Group (funded by argenx) and Victoria Golub (argenx).
Declarations
Ethics approval and consent to participate: As described in the original publication, the ADHERE trial was conducted in accordance with the protocol and consensus ethical principles derived from international guidelines, including the Declaration of Helsinki, Council for International Organizations of Medical Sciences International Ethical Guidelines, applicable International Council for Harmonization of Technical Requirements for Pharmaceuticals for Human Use Good Clinical Practice Guidelines, and other applicable laws and regulations. The protocol was approved by an institutional review board or independent ethics committees at each participating site.
Consent for publication: Not applicable.
Author contributions: Jeffrey A. Allen: conceptualization, investigation, methodology, validation, writing – original draft, writing – review and editing.
Luis Querol: investigation, writing – original draft, writing – review and editing.
Niraja Suresh: investigation, writing – original draft, writing – review and editing.
Anneleen Remmerie: investigation, supervision, project administration, formal analysis, methodology, validation, writing – original draft, writing – review and editing.
Trevor Mole: investigation, supervision, formal analysis, methodology, validation, writing – original draft, writing – review and editing.
Kelly McCoy: writing – original draft, writing – review and editing.
Lisa Butler: writing – original draft, writing – review and editing.
Benjamin van Hoorick: investigation, supervision, formal analysis, methodology, validation, writing – original draft, writing – review and editing.
Satoshi Kuwabara: investigation, writing – original draft, writing – review and editing.
Pieter A. van Doorn: conceptualization, methodology, investigation, validation, writing – original draft, writing – review and editing.
Richard A. Lewis: conceptualization, methodology, investigation, writing – original draft, writing – review and editing.
Funding: The ADHERE trial was sponsored by argenx.
Competing interests: Jeffrey A. Allen reports consulting fees from Akcea Therapeutics, Alexion, Alnylam, Annexon Biosciences, argenx, CSL Behring, Grifols, Immunovant, ImmuPharma, Johnson & Johnson, and Takeda, and payment or honoraria for lectures, presentations, speakers bureaus, manuscript writing or educational events from Alnylam, Annexon Biosciences, argenx, CSL Behring, and Takeda.
Luis Querol reports grants or contracts from argenx, CIBERER, Instituto de Salud Carlos III–Ministry of Economy and Innovation (Spain), and UCB; consulting fees from Annexon Biosciences, Alnylam, argenx, Avilar Therapeutics, CSL Behring, Dianthus Therapeutics, Janssen, LFB, Novartis, Nuvig Therapeutics, Roche, Sanofi, and Takeda; payment or honoraria for lectures, presentations, speakers bureaus, manuscript writing, or educational events from Alnylam, argenx, CSL Behring, Novartis, Roche, and Sanofi; support for attending meetings and travel from Alnylam and Sanofi; participation on a data safety monitoring board or advisory board for argenx, CSL Behring, Sanofi, and UCB; and a leadership or fiduciary role in other board, society, committee, or advocacy group, paid or unpaid, for Inflammatory Neuropathy Consortium and Peripheral Nerve Society.
Niraja Suresh reports payment or honoraria for lectures, presentations, speakers bureaus, manuscript writing, or educational events from Alnylam, and participation on a data safety monitoring board or advisory board for Takeda.
Anneleen Remmerie, Trevor Mole, and Benjamin van Hoorick are employees of argenx.
Kelly McCoy and Lisa Butler are employees of the GBS|CIDP Foundation.
Satoshi Kuwabara declares no competing interests.
Pieter A. van Doorn reports support for attending meetings and travel, participation on a data safety monitoring board or advisory board from argenx, and payment or honoraria for consulting or steering committees for Annexon, Hansa Biopharma, Octapharma and Sanofi.
Richard A. Lewis reports royalties or licenses from UpToDate; consulting fees from Annexon Biosciences, argenx, CSL Behring, Dianthus Therapeutics, Grifols, Immunovant, Janssen, Nuvig Therapeutics, Sanofi, and Takeda; payment or honoraria for lectures, presentations, speakers bureaus, manuscript writing, or educational events from argenx, CSL Behring, Medscape, and Sanofi; participation on a data safety monitoring board or advisory board for Boehringer Ingelheim and Novartis; and leadership or fiduciary role in other board, society, committee, or advocacy group, paid or unpaid, for Peripheral Nerve Society and GBS-CIDP Foundation International.
Availability of data and materials: argenx is committed to responsible data sharing regarding the clinical trials it funds. Included in this commitment is access to anonymized individual-level and trial-level data (analysis data sets), and other information (eg, protocols and clinical study reports), as long as the trial is not part of an ongoing or planned regulatory submission. These clinical trial data can be requested by qualified researchers who engage in rigorous independent scientific research and will only be provided after review and approval of a research proposal and statistical analysis plan, and execution of a data sharing agreement. Data requests can be submitted at any time, and the data will be accessible for 12 months. Requests can be submitted to esr@argenx.com.