A common clinical observation is that patients who develop significant immune-related toxicities, like colitis or pneumonitis, are frequently the same ones who experience the most profound and durable responses to checkpoint inhibitor therapy.

The primary goal after managing immune checkpoint inhibitor (ICI)-induced ITP is resuming cancer therapy. Data shows most patients do not experience a relapse of ITP upon re-challenge with the ICI, allowing them to continue their effective cancer treatment.

The distinct side effect profiles of pan-RAS inhibitors (rash, mucositis) and G12D-specific inhibitors (GI issues) are driving separate clinical strategies. The G12D drugs' better combinability with chemotherapy contrasts with pan-RAS agents, which may be better suited for monotherapy due to toxicity from blocking normal RAS.

A key clinical strategy for managing the TKI Zongertinib is proactive liver function monitoring. Checking AST/ALT every two weeks for the first three months allows clinicians to intervene with dose holds at the first sign of mild elevations, thereby preventing severe toxicity that would mandate a dose reduction.

The combination of the KRAS G12C inhibitor Sotorasib with immunotherapy, a seemingly logical approach, has been abandoned. Clinical trials were closed due to unacceptable levels of hepatotoxicity (liver damage), particularly in patients who had recently received immunotherapy. This demonstrates an unexpected and clinically significant negative drug-drug interaction, serving as a cautionary tale for future combination studies.

When a patient on lenvatinib and pembrolizumab develops diarrhea, the first diagnostic step is to pause lenvatinib. If the diarrhea resolves, it's likely from the TKI. If it persists, it's more likely immune-mediated colitis from pembrolizumab, requiring different management like steroids. This simple step clarifies the cause.

For patients with actionable mutations like EGFR or ALK, targeted therapy is the priority, regardless of PD-L1 score. Starting immunotherapy first in these patients can significantly increase the risk of developing severe pneumonitis (ILD) when they later switch to targeted therapy like osimertinib.

Data shows that patients who permanently stopped ipilimumab due to immune-related side effects still had exceptionally good outcomes. This gives clinicians confidence to manage toxicity by discontinuing the CTLA-4 inhibitor portion of the regimen while continuing nivolumab, without fearing a loss of efficacy.

When a toxicity like rash occurs with EV+pembrolizumab—which could be caused by either drug—the recommended strategy is to stop both. After the rash improves, reintroduce the drug least suspected of causing it first. If the rash does not recur, it helps confirm the other agent was the culprit.