What the label lists and what reports show
Inavolisib side effects
Inavolisib's FDA label: “The most common (≥ 20%) adverse reactions, including laboratory abnormalities, were decreased neutrophils, decreased hemoglobin, increased fasting glucose, decreased platelets, decreased lymphocytes, stomatitis, diarrhea, decreased calcium, fatigue, decreased …” FAERS holds 527 reports naming it through July 30, 2026; the reaction reported most often, leaving out the conditions it is used for, product-use terms and outcomes, is hyperglycaemia (133 reports).
- No generic listed
Check it at the source: the inavolisib FDA label on DailyMed (effective April 21, 2026, Genentech, Inc.); the FDA FAERS public dashboard.
What does the patient leaflet say about side effects?
From the patient leaflet: What are the possible side effects of ITOVEBI?ITOVEBI may cause serious side effects, including: High blood sugar levels (hyperglycemia). High blood sugar is common with ITOVEBI, and may be severe or fatal. Untreated severe hyperglycemia can lead to a condition called diabetic ketoacidosis that can happen in people treated with ITOVEBI. Diabetic ketoacidosis is a serious condition that requires treatment in a hospital and that can lead to death. Your healthcare provider will monitor your blood sugar levels before you start and during treatment with ITOVEBI. Your blood sugar levels may be monitored more often if you have a history of Type 2 diabetes. Your healthcare provider may also ask you to self-monitor and report your blood sugar levels at home. This will be required more frequently in the first 4 weeks of treatment. If you are not sure how to test your blood sugar levels, talk to your healthcare provider. […]
Source: FDA drug label, Genentech, Inc., effective April 21, 2026 (SPL set 5de59f5b-e5db-410f-b692-658686ef4107), via openFDA; the full label on DailyMed
What does the label list?
From the label: adverse reactionsThe most common (≥ 20%) adverse reactions, including laboratory abnormalities, were decreased neutrophils, decreased hemoglobin, increased fasting glucose, decreased platelets, decreased lymphocytes, stomatitis, diarrhea, decreased calcium, fatigue, decreased potassium, increased creatinine, increased ALT, nausea, decreased sodium, decreased magnesium, rash, decreased appetite, COVID-19 infection, and headache.
Table 3: Adverse Reactions (≥ 10% with ≥ 5% [All Grades] or ≥ 2% [Grade 3-4] Higher Incidence in the ITOVEBI Arm) in INAVO120
| Reaction | All Grades (%) | Grade 3-4 (%) | All Grades (%) | Grade 3-4 (%) |
|---|---|---|---|---|
| Stomatitis Includes aphthous ulcer, glossitis, glossodynia, lip ulceration, mouth… | 51 | 6 No Grade 4 adverse reactions were observed. | 27 | 0 |
| Diarrhea | 48 | 3.7 | 16 | 0 |
| Nausea | 28 | 0.6 | 17 | 0 |
| Vomiting | 15 | 0.6 | 5 | 1.2 |
| Fatigue | 38 | 1.9 | 25 | 1.2 |
| Rash Includes other related terms. | 26 | 0 | 19 | 0 |
| Alopecia | 19 | 0 | 6 | 0 |
| Dry skin Includes dry skin, skin fissures, xerosis, and xeroderma. | 13 | 0 | 4.3 | 0 |
| Decreased appetite | 24 | 0 | 9 | 0 |
| COVID-19 infection | 23 | 1.9 | 11 | 0.6 |
| Urinary tract infection | 15 | 1.2 | 9 | 0 |
| Headache | 22 | 0 | 14 | 0 |
| Decreased weight | 17 | 3.7 | 0.6 | 0 |
Rows and numbers as the label prints them, under its own column headings (the first rows of a longer table where it runs on). A reaction in a trial table is not necessarily caused by the medicine, and trials differ from everyday use.
From the label: adverse reactions, continuedThe following adverse reactions are discussed in greater detail in other sections of the label: Hyperglycemia [see Warnings and Precautions (5.1) ] Stomatitis [see Warnings and Precautions (5.2) ] Diarrhea [see Warnings and Precautions (5.3) ] The most common (≥ 20%) adverse reactions, including laboratory abnormalities, were decreased neutrophils, decreased hemoglobin, increased fasting glucose, decreased platelets, decreased lymphocytes, stomatitis, diarrhea, decreased calcium, fatigue, decreased potassium, increased creatinine, increased ALT, nausea, decreased sodium, decreased magnesium, rash, decreased appetite, COVID-19 infection, and headache. ( 6.1 ) To report SUSPECTED ADVERSE REACTIONS, contact Genentech at 1-888-835-2555 or FDA at 1-800-FDA-1088 or www.fda.gov/medwatch. 6.1 Clinical Trial Experience Because clinical trials are conducted under widely varying conditions, adverse reaction rates observed in the clinical trials of a drug cannot be directly compared to rates in the clinical trials of another drug and may not reflect the rates observed in practice. Locally Advanced or Metastatic Breast Cancer INAVO120 The safety of ITOVEBI was evaluated in a randomized, double-blind, placebo-controlled study (INAVO120) in 324 patients with PIK3CA -mutated, HR-positive, HER2-negative, locally advanced or metastatic breast cancer [see Clinical Studies (14.1) ]. …
Source: FDA drug label, Genentech, Inc., effective April 21, 2026 (SPL set 5de59f5b-e5db-410f-b692-658686ef4107), via openFDA; the full label on DailyMed
What do FAERS reports show?
527 reports list inavolisib among the medicines taken, each a report of something that happened, not proof the medicine caused it; 25 are coded as a death and 177 as a hospital stay. Counts follow how widely a medicine is used and watched, and they are not a measure of how risky it is. Of the 23 reactions below, 18 are named by the same term (in US spelling) in the label's adverse reactions, warnings or patient leaflet; a reaction the label does not name may still be there under another word, and a report does not show that the medicine caused it.
Reports received each year
The 25 most reported reactions
Source: FDA Adverse Event Reporting System (FAERS) via openFDA, reports through July 30, 2026; reactions as MedDRA preferred terms
What next?
- Inavolisib: the full record
- label, generics, price, shortages, recalls
- Report a side effect to the FDA
- MedWatch
- Side effects hub
- the most reported medicines and reactions