Home › Trials › NCT05655078

Proton therapy for treating malignant pleural mesothelioma

Hemithoracic Irradiation With Proton Therapy in Malignant Pleural Mesothelioma

Not applicable Interventional University College, London · NCT05655078

This study is testing if proton therapy can help people with malignant pleural mesothelioma live longer and feel better compared to standard care.

Quick facts

PhaseNot applicable
Study typeInterventional
Enrollment148 (estimated)
Ages18 Years and up
SexAll
SponsorUniversity College, London Academic / other
Drugs / interventionschemotherapy, immunotherapy, nivolumab, ipilimumab
Locations25 sites (Eastbourne, East Sussex and 24 other locations)
Trial IDNCT05655078 on ClinicalTrials.gov

What this trial studies

This clinical trial is a randomized phase III trial designed for patients with unilateral malignant pleural mesothelioma (MPM). Participants will be randomly assigned to receive either proton beam therapy (PBT) targeting the hemithorax or standard care with active surveillance. The primary endpoints include progression-free survival and overall survival, while secondary endpoints assess safety, tolerability, and quality of life. Patients will be followed for two years post-randomization to evaluate treatment outcomes.

Who should consider this trial

Good fit: Ideal candidates are adults aged 18 and older with histologically confirmed unilateral malignant pleural mesothelioma and adequate pulmonary function.

Not a fit: Patients with metastatic disease, prior thoracic treatments, or those requiring immediate systemic therapy may not benefit from this study.

Why it matters

Potential benefit: If successful, this treatment could improve survival rates and quality of life for patients with malignant pleural mesothelioma.

How similar studies have performed: Other studies using proton therapy for various cancers have shown promising results, suggesting potential success for this novel approach in treating MPM.

Eligibility criteria

Show full inclusion / exclusion criteria 
Inclusion criteria:

* Patients ≥18 years of age, with biopsy confirmed MPM and histological subtyping (epithelioid or non-epithelioid)
* N0 or N1 and M0 disease
* Written informed consent
* Patient and local/regional MDT opt for active surveillance and deferral of SACT until clinical or radiological progression
* WHO Performance Status 0-1
* Disease confined to one hemithorax based on CT assessment
* Adequate pulmonary function

  * ≥ 40% predicted post-FEV1;
  * ≥ 40% predicted DLCO/TLCO
* Agreement to travel to either proton beam therapy centres (i.e. UCLH or The Christie) if randomised to arm 2
* Agreement to be followed up at a local HIT-Meso trial site
* Patient likely able to complete PBT planning based on local assessment

Exclusion criteria:

* Presence of metastatic or contralateral disease
* Cytological diagnosis and/or undetermined histological subtype
* Prior thoracic radiotherapy, chemotherapy, immunotherapy for MPM
* Prior radical surgery for MPM (extrapleural pneumonectomy or extended pleurectomy decortication or pleurectomy decortication)
* Initial systemic therapy or surgery is required and the patient and local/regional MDT do not opt for active surveillance
* Involvement of contralateral or supraclavicular lymph nodes
* T4 disease with invasion of the myocardium
* N2 and/or M1 disease
* Presence of new effusion that is not amenable to drainage
* WHO Performance Status ≥ 2
* Women who are pregnant or breast feeding
* Current or previous malignant disease which may impact on the patient's life expectancy
* Patient fitted with a pacemaker or implantable cardioverter-defibrillator (ICD)\\
* Diagnosis of clinically significant interstitial lung disease (ILD), excluding mild fibrosis or incidental findings
* Chronic non-malignant disease with an estimated three-year survival rate of less than 20%
* Patient with prior thoracic / abdominal radiotherapy for malignancy who was not discussed with sponsor before recruitment

Where this trial is running

Eastbourne, East Sussex and 24 other locations

Study contacts

How to participate

  1. Review the eligibility criteria above with your treating physician.
  2. Visit the official trial page on ClinicalTrials.gov for the most current contact information and recruitment status.
  3. Contact the listed study coordinator or principal investigator to request pre-screening. Pre-screening is free and never obligates you to enroll.
View on ClinicalTrials.gov → Find more trials like this →
Conditions Malignant Pleural MesotheliomaProton beam therapy
Last reviewed 2026-06-13 by the Find a Trial editorial team. Information on this page is for educational purposes and is not medical advice. Always consult qualified healthcare professionals about clinical trial participation.