For U.S. Healthcare Professionals

Recommended dosage modifications for LYTGOBI adverse reactions1



Dose Modifications

Serum phosphate
≥5.5 - ≤7.0 mg/dL

Continue LYTGOBI at the current dose and initiate phosphate-lowering therapy.
Monitor serum phosphate weekly

Serum phosphate
>7.0 - ≤10.0 mg/dL

Initiate or adjust phosphate-lowering therapy and monitor serum phosphate weekly and

Reduce LYTGOBI to next lower dose

  • If the serum phosphate resolves to ≤7.0 mg/dL within 2 weeks after dose reduction, continue at this reduced dose
  • If serum phosphate is not ≤7.0 mg/dL within 2 weeks, further reduce LYTGOBI to the next lower dose
  • If serum phosphate is not ≤7.0 mg/dL within 2 weeks after the second dose reduction, withhold LYTGOBI until serum phosphate is ≤7.0 mg/dL and resume at the dose prior to suspending

Serum phosphate
>10.0 mg/dL

Initiate/intensify phosphate-lowering therapy and monitor serum phosphate weekly and

Withhold LYTGOBI until phosphate is ≤7.0 mg/dL and resume LYTGOBI at the next lower dose

  • Permanently discontinue LYTGOBI if serum phosphate is not ≤7.0 mg/dL within 2 weeks following 2 dose interruptions and reductions


Dose Modifications

Retinal pigment epithelial detachment

Not applicable

Continue LYTGOBI at current dose and continue periodic ophthalmic evaluation

  • If resolving within 14 days, continue LYTGOBI at the current dose
  • If not resolving within 14 days, withhold LYTGOBI until resolving; then resume LYTGOBI at previous or a lower dose


Dose Modifications

Other adverse reactions

Grade 3a

Withhold LYTGOBI until toxicity resolves to Grade 1 or baseline, then resume

  • For hematological toxicities resolving within 1 week, resume at the dose prior to suspending
  • For other ARs, resume at the next lower dose

Grade 4a

Permanently discontinue LYTGOBI

  • aSeverity as defined by NCI CTCAE 4.03

Alternative DosePaks are available to support dose modifications

Recommended dose reductions for adverse reaction management:

  • First dose reductionb: 16 mg (four 4-mg tablets) orally once daily (28 count pack)
  • Second dose reductionb12 mg (three 4-mg tablets) orally once daily (21 count pack)
  • bPermanently discontinue LYTGOBI if unable to tolerate 12 mg once daily.
LYTGOBI® (futibatinib) tablets 28 tablet DosePak

28 count

LYTGOBI® (futibatinib) tablets 21 tablet DosePak

21 count

AR=adverse reaction; CTCAE=Common Terminology Criteria for Adverse Events; NCI=National Cancer Institute; RPED=retinal pigment epithelial detachment.



LYTGOBI [package insert]. Princeton, NJ: Taiho Oncology, Inc.; 2022.



LYTGOBI is indicated for the treatment of adult patients with previously treated, unresectable, locally advanced or metastatic intrahepatic cholangiocarcinoma harboring fibroblast growth factor receptor 2 (FGFR2) gene fusions or other rearrangements.

This indication is approved under accelerated approval based on overall response rate and duration of response. Continued approval for this indication may be contingent upon verification and description of clinical benefit in a confirmatory trial(s).



  • Ocular Toxicity: LYTGOBI can cause Retinal Pigment Epithelial Detachment (RPED), which may cause symptoms such as blurred vision. RPED occurred in 9% of 318 patients who received LYTGOBI across clinical trials. The median time to first onset of RPED was 40 days. RPED led to dose interruption of LYTGOBI in 1.3% of patients, dose reduction in 1.6% of patients, and permanent discontinuation in 0.3% of patients. Perform a comprehensive ophthalmological examination, including optical coherence tomography (OCT) of the macula, prior to initiation of therapy, every 2 months for the first 6 months, and every 3 months thereafter. For onset of visual symptoms, refer patients for ophthalmologic evaluation urgently, with follow-up every 3 weeks until resolution or discontinuation of LYTGOBI. Withhold or reduce the dose of LYTGOBI as recommended. Dry Eye/Corneal Keratitis: Among 318 patients who received LYTGOBI across clinical trials, dry eye occurred in 15% of patients. Treat patients with ocular demulcents as needed.
  • Hyperphosphatemia and Soft Tissue Mineralization: LYTGOBI can cause hyperphosphatemia leading to soft tissue mineralization, calcinosis, nonuremic calciphylaxis, and vascular calcification. Hyperphosphatemia was reported in 88% of 318 patients treated with LYTGOBI across clinical trials with a median time of onset of 5 days (range 3‑117). Phosphate binders were received by 77% of patients who received LYTGOBI. Monitor for hyperphosphatemia throughout treatment. Initiate a low-phosphate diet and phosphate-lowering therapy when serum phosphate level is ≥5.5 mg/dL; initiate or intensify phosphate-lowering therapy when >7 mg/dL; reduce dose, withhold, or permanently discontinue LYTGOBI based on duration and severity of hyperphosphatemia.
  • Embryo-fetal Toxicity: Based on findings in an animal study and its mechanism of action, LYTGOBI can cause fetal harm when administered to a pregnant woman. Advise pregnant women of the potential risk to the fetus. Advise female patients of reproductive potential, and males with female partners of reproductive potential, to use effective contraception during treatment with LYTGOBI and for 1 week after the last dose.

  • Serious adverse reactions occurred in 39% of patients receiving LYTGOBI, and in ≥2% of patients included pyrexia, gastrointestinal hemorrhage, ascites, musculoskeletal pain, and bile duct obstruction.
  • The most common adverse reactions (≥20%) were nail toxicity, musculoskeletal pain, constipation, diarrhea, fatigue, dry mouth, alopecia, stomatitis, abdominal pain, dry skin, arthralgia, dysgeusia, dry eye, nausea, decreased appetite, urinary tract infection, palmar-plantar erythrodysesthesia syndrome, and vomiting.
  • The most common laboratory abnormalities (≥20%) were increased phosphate, increased creatinine, decreased hemoglobin, increased glucose, increased calcium, decreased sodium, decreased phosphate, increased alanine aminotransferase, increased alkaline phosphatase, decreased lymphocytes, increased aspartate aminotransferase, decreased platelets, increased activated partial thromboplastin time, decreased leukocytes, decreased albumin, decreased neutrophils, increased creatine kinase, increased bilirubin, decreased glucose, increased prothrombin international normalized ratio, and decreased potassium.

  • Dual P-gp and Strong CYP3A Inhibitors: Avoid concomitant use of drugs that are dual P-gp and strong CYP3A inhibitors.
  • Dual P-gp and Strong CYP3A Inducers: Avoid concomitant use of drugs that are dual P-gp and strong CYP3A inducers.

  • Lactation: Because of the potential for serious adverse reactions from LYTGOBI in breastfed children, advise women not to breastfeed during treatment and for 1 week after the last dose.

Please see accompanying full Prescribing Information for complete details.