IORBC are pleased to share information about the publication of a trial by Kamtam et al - the first-in-human, prospective clinical trial of stereotactic radiation for lung volume reduction (SILVR) for severe emphysema.

Emphysema is a subtype of chronic obstructive pulmonary disease and a “major public health concern”, with substantial morbidity and mortality. Emphysema has a significant effect on quality of life and better treatments are clearly needed. Some patients require lung volume reduction, which is generally done with surgery or endobronchial valves. But not all patients are able to tolerate such treatments and this is the patient group where SILVR was used.

The single-arm, prospective clinical trial treated eligible patients with severe emphysema with unilateral stereotactic ablative radiation therapy (45 Gy in 3 fractions) to a target within the most emphysematous region. The primary outcome was safety in terms of incidence of grade ≥3 adverse events, and the secondary outcome was efficacy.

The trial results noted that eight patients received the intervention and the median (range) baseline characteristics were:

• Age 73 years (63-78)

• FEV1%1¹ = 28.5% (19.0-42.0)

• Diffusing capacity of the lungs for carbon monoxide percent of predicted value 40% (24.0-67.0)

• BODE index (Body mass index, airflow obstruction, dyspnea, and exercise capacity) = 5.5 (5-9).

The incidence of grade ≥3 adverse events was 37.5% (3 of 8 patients) whilst the mean relative change in target lobe volume was -23.1% at 6 months and -26.5% at 18 months.

Kamtam et al conclude that these results provide evidence of acceptable safety and a preliminary signal of efficacy of SILVR in patients, and that the therapy appears particularly appropriate for patients with BODE index ≤5.

They further state their belief that with additional prospective study adequately powered to demonstrate efficacy, SILVR may become established as an effective treatment for patients with severe COPD.

As a next step, Kamtam et al propose that future larger prospective phase II clinical trials are appropriate - potentially focusing on patients with BODE index ≤5, homogeneous disease, and/or a substantial component of airways disease.

To read the full clinical investigation, please visit the link below:

Clinical Trial of Stereotactic Irradiation to Achieve Lung Volume Reduction (SILVR) in Severe Emphysema

¹(Forced expiratory volume in 1 second percent of predicted value)

Authors:

Devanish N Kamtam MBBS, MS, Michael S Binkley MD, MS, Ntemena Kapula MAS, Cheyenne Sadeghi BS, Shannon Nesbit BS, Haiwei Henry Guo MD PhD, Joon Chang MD, Peter G Maxim PhD, Maximilian Diehn MD, PhD, Billy W Loo Jr MD, PhD, Joseph B Shrager MD, First in human Phase I Clinical Trial of Stereotactic Irradiation to Achieve Lung Volume Reduction (SILVR) in Severe Emphysema, International Journal of Radiation Oncology,

Biology, Physics (2024), doi: https://doi.org/10.1016/j.ijrobp.2024.03.049