Last reviewed 2026-05-13 · How we verify

Itovebi (inavolisib)

Inavolisib is a PI3K inhibitor with degradative activity against PI3Kα.

Inavolisib, developed by Pfizer Inc., is a PI3K inhibitor with degradative activity against PI3Kα. It is used for the treatment of relapsed or refractory advanced follicular lymphoma, marginal zone lymphoma, and diffuse large B-cell lymphoma. Inavolisib's mechanism of action involves the degradation of mutated PI3K catalytic alpha subunit p110α, inhibition of AKT phosphorylation, and induction of apoptosis. The drug has shown clinical differentiation in PIK3CA-mutated breast cancer models. Inavolisib's commercial significance lies in its potential to address unmet needs in lymphoma treatment. Pfizer's pipeline developments indicate ongoing research into inavolisib's efficacy and safety.

At a glance

Mechanism of action

Inavolisib works by targeting the PI3K enzyme, specifically the PI3Kα subunit. This enzyme is involved in cell signaling pathways that promote cell growth and survival. By inhibiting PI3Kα, inavolisib disrupts these pathways, leading to the degradation of the mutated enzyme and the induction of apoptosis in cancer cells. This mechanism of action is particularly effective in treating cancers with PIK3CA mutations.

Approved indications

• Relapsed or refractory advanced follicular lymphoma (FL) after at least two prior lines of therapy for whom MAb-based therapy has failed
• Relapsed or refractory marginal zone lymphoma (MZL) after at least two prior lines of therapy for whom MAb-based therapy has failed
• Relapsed or refractory diffuse large B-cell lymphoma (DLBCL) after at least two prior lines of therapy for whom MAb-based therapy has failed

Common side effects

• Stomatitis
• Diarrhea
• Nausea
• Fatigue
• Rash
• Decreased appetite
• COVID-19 infection
• Urinary tract infection
• Headache
• Decreased weight
• Hyperglycemia
• Neutropenia

Drug interactions

• Bupropion
• CYP3A4 inhibitors
• CYP3A4 inducers
• Warfarin
• CYP2D6 inhibitors
• CYP2D6 inducers
• P-gp inhibitors
• P-gp inducers

Key clinical trials

• A Study to Evaluate the Effectiveness and Safety of Inavolisib in Participants With Endocrine-resistant, PIK3CA-mutated, Hormone Receptor-positive, HER2-negative Locally Advanced or Metastatic Breast Cancer
• A Study Evaluating Single-agent Inavolisib, Inavolisib Plus Atezolizumab, and Inavolisib Plus Pembrolizumab in PIK3CA-Mutated Cancers (PHASE1)
• A Study Evaluating the Efficacy and Safety of Inavolisib + Palbociclib + Fulvestrant vs Placebo + Palbociclib + Fulvestrant in Participants With PIK3CA-Mutant, Hormone Receptor-Positive, HER2-Negative, Locally Advanced or Metastatic Breast Cancer (PHASE2, PHASE3)
• A Study Evaluating the Efficacy and Safety of Multiple Treatment Combinations in Participants With Breast Cancer (PHASE1, PHASE2)
• A Study Evaluating the Efficacy and Safety of Multiple Treatment Combinations in Patients With Metastatic or Locally Advanced Breast Cancer (PHASE1, PHASE2)
• To Study the Effect of Inavolisib in Combination With Fulvestrant in Participants With Breast Cancer (PHASE2)
• A Rollover Study for Participants Previously Enrolled in a Genentech and/or F. Hoffman-La Roche Sponsored Study (PHASE3)
• A Study to Evaluate the Effect of Moderate or Severe Hepatic Impairment on the Pharmacokinetics (PK) of Inavolisib (PHASE1)

Patents

Primary sources

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Competitive intelligence

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• Pfizer portfolio CI