How does Opdivo (nivolumab) work?
Opdivo is an immune checkpoint inhibitor. It blocks the PD-1 (programmed death-1) receptor on T cells, preventing tumor cells from turning those T cells off. By inhibiting PD-1 signaling, Opdivo helps the immune system recognize and attack cancer cells.
What is the PD-1/PD-L1 pathway, in plain terms?
Tumors can exploit PD-1 signaling to evade immune attack: when PD-1 on T cells engages PD-L1 (often found on tumor cells and other cells in the tumor environment), it dampens T-cell activity. Opdivo’s PD-1 blockade interrupts that “off switch,” which can restore or enhance T-cell responses against the tumor.
What kinds of cancers is Opdivo used for (mechanism-wise)?
Because Opdivo works by boosting T-cell activity through PD-1 blockade, it can be used across multiple cancer types where the PD-1/PD-L1 pathway contributes to immune escape. The exact indications depend on the specific cancer and treatment setting.
Why does Opdivo sometimes stop working?
A common reason immune checkpoint therapies lose effect over time is that tumors can develop alternative immune-evasion mechanisms besides PD-1/PD-L1, or the tumor environment may become less responsive to T-cell activation. Another factor is patient-to-patient variation in how strongly their tumors rely on PD-1 signaling.
What side effects come from the same mechanism?
Because Opdivo activates the immune system, it can also cause immune-related side effects when the immune response targets healthy tissues (for example, inflammation in organs such as the lungs, intestines, skin, liver, or endocrine glands). These effects are consistent with the drug’s action on T-cell activity.
How is Opdivo given, and does the mechanism affect dosing?
Opdivo is given by IV infusion. The dosing schedule is set by the approved regimen for each cancer type and treatment context, even though the underlying mechanism is the same (PD-1 blockade).
How does Opdivo differ from other checkpoint drugs?
Opdivo targets PD-1. Other checkpoint therapies can target different immune checkpoints (for example, CTLA-4 inhibitors), which changes the aspect of T-cell regulation being modified. Combining or choosing agents can depend on how the different pathways influence tumor immune escape.