From the Guidelines
The typical onset of monoclonal antibody (mAb) induced pneumonitis generally occurs within the first few months of treatment, with a median time to onset of 34 weeks, though it can range from 1.5 to 127 weeks. This timing can vary depending on the specific monoclonal antibody being used and the underlying condition of the patient, such as pre-existing lung disease or prior thoracic radiation. For example, in patients with non-small cell lung cancer (NSCLC), pneumonitis onset appears earlier, with a median of 2.1 months, compared to patients with melanoma, where the median onset is 5.2 months 1. The onset can be insidious with gradually worsening dyspnea and dry cough, or it may present more acutely with rapid respiratory deterioration.
Key Considerations
- The pathophysiology involves immune-mediated inflammation of lung tissue triggered by the monoclonal antibody therapy, leading to various radiographic patterns including ground-glass opacities, consolidations, or interstitial changes on imaging studies 1.
- Clinicians should maintain vigilance throughout treatment but particularly during the first few months when risk appears highest.
- Risk factors that may influence earlier onset include prior thoracic radiation, pre-existing lung disease, and concurrent use of other pneumotoxic medications.
- Presenting symptoms related to immune therapy–induced pneumonitis may include new or worsening cough, shortness of breath, increased oxygen requirement, chest pain, and/or fever 1.
Management and Recommendations
- Refer to the latest guidelines for the management of immune-related adverse events in patients treated with immune checkpoint inhibitor therapy, which includes recommendations for identification, evaluation, and management of lung toxicities 1.
- It is crucial to monitor patients closely for signs of pneumonitis and to intervene early to prevent severe outcomes, considering the potential for pneumonitis to be one of the most common causes of immune checkpoint inhibitor-related death 1.
From the Research
Onset of Monoclonal Antibody Pneumonitis
- The onset of monoclonal antibody (mAb) induced pneumonitis can vary, with some cases occurring during treatment and others after treatment discontinuation 2, 3.
- Acute-onset pneumonitis has been reported during the first dose of durvalumab, an anti-PD-L1 monoclonal antibody 2.
- Late-onset pneumonitis has also been reported after cessation of nivolumab or pembrolizumab treatment, with one case occurring 7 months after the final administration of nivolumab 3.
- The median time frame for the appearance of pembrolizumab-associated pneumonitis is 2.8 months, but it can occur as early as 48 hours after treatment initiation 4.
- Immune-related pneumonitis can be recurrent, and low-dose glucocorticoids may be necessary to prevent recurrence and control the development of pneumonitis 5.
Timing of Onset
- The timing of onset can range from acute (within 48 hours) to late (several months after treatment discontinuation) 2, 3, 4.
- The exact timing of onset may depend on various factors, including the specific monoclonal antibody used, the dose and duration of treatment, and individual patient characteristics.