What the label lists and what reports show
Avutometinib and defactinib side effects
Avutometinib and defactinib's FDA label: “The most common (≥ 25%) […]” FAERS holds 794 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 fatigue (118 reports).
- No generic listed
Check it at the source: the avutometinib and defactinib FDA label on DailyMed (effective May 1, 2025, Verastem 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 AVMAPKI FAKZYNJA CO-PACK?AVMAPKI FAKZYNJA CO-PACK may cause serious side effects, including: eye problems. Eye problems are common with AVMAPKI FAKZYNJA CO-PACK and can be severe. Your healthcare provider will send you to see an eye care professional before starting treatment, during treatment, and for any new or worsening eye problems. Tell your healthcare provider if you get any new or worsening eye problems including: changes in vision, such as blurred vision, double vision, or vision loss dry eye(s) eye and eyelid inflammation, including redness, swelling, and itching eye pain new or increased floaters (small dark spots or squiggly lines that float across your vision) light hurting eyes or seeing flashes of light severe skin reactions. Skin reactions are common with AVMAPKI FAKZYNJA CO-PACK and can be severe or life threatening. […]
Source: FDA drug label, Verastem Inc., effective May 1, 2025 (SPL set 65889527-1406-45df-8a85-e2690dcf427d), via openFDA; the full label on DailyMed
What does the label list?
From the label: adverse reactionsThe most common (≥ 25%) […]
Table 3 Adverse Reactions (≥10%) in Patients with KRAS-Mutated Recurrent LGSOC who Received AVMAPKI FAKZYNJA CO-PACK in RAMP-201 Severity as defined by National Center Institute Common Terminology Criteria for Adverse…
| Reaction | Adverse Reaction All Grades % | AVMAPKI FAKZYNJA CO-PACK N = 57 Grade 3 or 4 No Grade 4 treatment-emergent adverse events occurred. % |
|---|---|---|
| Nausea | 74 | 1.8 |
| Diarrhea | 68 | 7 |
| Vomiting | 49 | 3.5 |
| Abdominal pain Includes multiple terms | 39 | 1.8 |
| Dyspepsia | 37 | 0 |
| Stomatitis | 35 | 3.5 |
| Constipation | 30 | 0 |
| Dry mouth | 18 | 0 |
| Decreased Weight | 11 | 0 |
| Fatigue | 72 | 3.5 |
| Edema | 67 | 1.8 |
| Rash Includes: butterfly rash, dermatitis, drug eruption, erythema, rash, rash… | 72 | 3.5 |
| Dermatitis acneiform Includes: acne, dermatitis acneiform, folliculitis, perioral… | 37 | 5.3 |
| Pruritus | 35 | 1.8 |
| Dry skin | 30 | 0 |
| Alopecia | 23 | 0 |
| Photosensitivity | 16 | 0 |
| Musculoskeletal pain | 68 | 1.8 |
| Joint swelling | 11 | 0 |
| Vitreoretinal disorders Includes: chorioretinopathy, detachment of retinal pigment… | 37 | 3.5 |
| Visual impairment Includes: asthenopia, astigmatism, halo vision, metamorphopsia,… | 35 | 0 |
| Dry eye | 12 | 0 |
| Dyspnea | 26 | 5.3 |
| Cough | 25 | 0 |
| Dizziness | 23 | 1.8 |
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 more detail in other sections of the labeling: Ocular Toxicities [see Warnings and Precautions (5.1) ] Serious Skin Toxicities [see Warnings and Precautions (5.2) ] Hepatotoxicity [see Warnings and Precautions (5.3) ] Rhabdomyolysis [see Warnings and Precautions (5.4) ] The most common (≥ 25%) adverse reactions, including laboratory abnormalities, were increased creatine phosphokinase, nausea, fatigue, increased aspartate aminotransferase, rash, diarrhea, musculoskeletal pain, edema, decreased hemoglobin, increased alanine aminotransferase, vomiting, increased blood bilirubin, increased triglycerides, decreased lymphocyte count, abdominal pain, dyspepsia, dermatitis acneiform, vitreoretinal disorders, increased alkaline phosphatase, stomatitis, pruritus, visual impairment, decreased platelet count, constipation, dry skin, dyspnea, cough, urinary tract infection, and decreased neutrophil count. ( 6.1 ) To report SUSPECTED ADVERSE REACTIONS, contact Verastem at 1-833-633-8786 or FDA at 1-800-FDA-1088 or www.fda.gov/medwatch. 6.1 Clinical Trials 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.
Source: FDA drug label, Verastem Inc., effective May 1, 2025 (SPL set 65889527-1406-45df-8a85-e2690dcf427d), via openFDA; the full label on DailyMed
What do FAERS reports show?
794 reports list avutometinib and defactinib among the medicines taken, each a report of something that happened, not proof the medicine caused it; 26 are coded as a death and 85 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 20 reactions below, 16 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?
- Avutometinib and defactinib: 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