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Rukobia Side Effects

Generic name: fostemsavir

Medically reviewed by Last updated on Apr 8, 2021.

Note: This document contains side effect information about fostemsavir. Some of the dosage forms listed on this page may not apply to the brand name Rukobia.

For the Consumer

Applies to fostemsavir: oral tablet extended release

Side effects requiring immediate medical attention

Along with its needed effects, fostemsavir (the active ingredient contained in Rukobia) may cause some unwanted effects. Although not all of these side effects may occur, if they do occur they may need medical attention.

Check with your doctor immediately if any of the following side effects occur while taking fostemsavir:

Less common

Side effects not requiring immediate medical attention

Some side effects of fostemsavir may occur that usually do not need medical attention. These side effects may go away during treatment as your body adjusts to the medicine. Also, your health care professional may be able to tell you about ways to prevent or reduce some of these side effects.

Check with your health care professional if any of the following side effects continue or are bothersome or if you have any questions about them:

More common

Less common

  • Belching
  • burning, numbness, tingling, or painful sensations
  • change in or loss of taste
  • difficulty in moving
  • dizziness
  • drowsiness
  • headache
  • heartburn
  • indigestion
  • joint pain or swelling
  • muscle pain, cramps, or stiffness
  • stomach discomfort, upset, or pain
  • trouble sleeping
  • unsteadiness or awkwardness
  • vomiting
  • weakness in the arms, hands, legs, or feet

For Healthcare Professionals

Applies to fostemsavir: oral tablet extended release


Most (81%) of the side effects reported were of mild or moderate severity. This drug was discontinued due to a side effect in 7% of patients at week 96; the most common side effects leading to discontinuation were related to infections. Serious drug reactions were reported in 3% of patients and included a few cases of severe immune reconstitution inflammatory syndrome.[Ref]


Very common (10% or more): Elevated creatinine (19%)[Ref]

Elevated creatinine (greater than 1.8 times the upper limit of normal [1.8 x ULN] or 1.5 times baseline) has been reported in 19% of patients.

Clinically relevant increases in serum creatinine have been reported primarily in patients with identifiable risk factors for reduced renal function, including preexisting medical history of renal disease and/or concomitant agents known to increase creatinine; a causal association between this drug and elevated serum creatinine was not established.[Ref]


Very common (10% or more): Elevated direct bilirubin (up to 14%), elevated ALT (up to 14%), elevated AST (up to 14%)

Common (1% to 10%): Elevated bilirubin[Ref]

Elevated direct bilirubin (greater than ULN), ALT (greater than 5 x ULN), and AST (greater than 5 x ULN) have each been reported in up to 14% of patients; elevated bilirubin (at least 2.6 x ULN) has been reported in up to 6% of patients.

Increases in direct (conjugated) bilirubin have been reported after treatment with this drug. Clinically significant cases were uncommon and were confounded by intercurrent serious comorbid events (e.g., sepsis, cholangiocarcinoma, other complications of viral hepatitis coinfection); in the remaining cases, elevations in direct bilirubin (without clinical jaundice) were generally transient, occurred without increases in liver transaminases, and resolved on continued therapy.

Grade 3 and 4 elevations in ALT and AST have each been reported in 14% of patients with hepatitis B and/or C virus coinfection compared with 3% (ALT) and 2% (AST) of patients without viral hepatitis coinfection; in some cases, these transaminase elevations were consistent with hepatitis B reactivation, especially when antihepatitis therapy was stopped.[Ref]


Elevated lipase (greater than 3 x ULN) has been reported in up to 10% of patients.[Ref]

Common (1% to 10%): Nausea, elevated lipase, diarrhea, abdominal pain (included abdominal discomfort, abdominal pain, upper abdominal pain), dyspepsia, vomiting[Ref]


Elevated triglycerides (greater than 500 mg/dL), cholesterol (at least 300 mg/dL), and LDL cholesterol (at least 190 mg/dL) have been reported in up to 10%, 5%, and 4% of patients, respectively.[Ref]

Common (1% to 10%): Elevated triglycerides, fatigue (included fatigue, asthenia), elevated cholesterol, elevated low-density lipoprotein (LDL) cholesterol[Ref]


Common (1% to 10%): Decreased neutrophils, decreased hemoglobin, decreased leukocytes[Ref]

Decreased neutrophils (up to 599 cells/mm3) and hemoglobin (less than 9 g/dL) have been reported in up to 7% and 6% of patients, respectively.[Ref]

Nervous system

Common (1% to 10%): Headache, somnolence

Frequency not reported: Dizziness, dysgeusia, peripheral neuropathy (included peripheral neuropathy, peripheral sensory neuropathy)[Ref]


Hyperglycemia (greater than 250 mg/dL) and elevated urate (greater than 12 mg/dL) have been reported in 4% and 3% of patients, respectively.[Ref]

Common (1% to 10%): Hyperglycemia, elevated urate[Ref]


Common (1% to 10%): Sleep disturbance (included insomnia, sleep deficit, sleep disorder, abnormal dreams)[Ref]


Common (1% to 10%): Rash (included rash, generalized rash, maculopapular rash, pruritic rash, allergic dermatitis)

Frequency not reported: Pruritus[Ref]


Common (1% to 10%): Immune reconstitution inflammatory syndrome[Ref]


Elevated creatine kinase (at least 10 x ULN) has been reported in 2% of patients.[Ref]

Common (1% to 10%): Elevated creatine kinase

Frequency not reported: Myalgia[Ref]


Frequency not reported: Prolonged ECG QT[Ref]

All reports of prolonged ECG QT were asymptomatic.[Ref]


1. "Product Information. Rukobia (fostemsavir)." ViiV Healthcare, Research Triangle Park, NC.

Further information

Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.

Some side effects may not be reported. You may report them to the FDA.