Sibeprenlimab-Szsi: uses, dosing, side effects & brands
Sibeprenlimab-Szsi is a medicine sold in the U.S. under one brand, for iga glomerulonephritis and proteinuria. Below: what the FDA label says, every product that contains it, what the pills look like, and its recall record.
Key facts
- Treats
- Iga Glomerulonephritis and Proteinuria
- Available as
- Injectable
- Sold as
- Voyxact
- Prescription?
- Prescription only
- Generic available?
- Not in our catalog
How sibeprenlimab-szsi is dosed
From the FDA label for Voyxact (application BLA761434). Other sibeprenlimab-szsi products — different forms, different strengths — are dosed differently. Follow the label for the one you were prescribed.
Recommended dosage: 400 mg injected subcutaneously once every 4 weeks. ( 2.1 ) 2.1 Recommended Dosage The recommended dosage of VOYXACT is 400 mg administered by subcutaneous injection once every 4 weeks. 2.2 Missed Dose If a scheduled dose of VOYXACT is missed, administer the missed dose as soon as possible and then resume dosing every 4 weeks thereafter. 2.3 Preparation and Administration VOYXACT is intended for patient self-administration or for administration by a caregiver. Provide proper training to patients and/or caregivers on the administration of VOYXACT prior to use according to the "Instructions for Use". Visually inspect the prefilled syringe for particulate matter and discoloration. The solution should be clear to opalescent and colorless to yellow. Do not use the prefilled syringe if the solution contains visible particulate matter, is cloudy or discolored (other than clear to opalescent, colorless to yellow). Allow VOYXACT prefilled syringe to come to room temperature up to 77°F (25°C) for 15 to 30 minutes before giving an injection. Keep VOYXACT prefilled syringe in the original carton to protect it from light. Once VOYXACT prefilled syringe has reached room temperature, do not return it to the refrigerator. Do not use VOYXACT if it has been at room temperature for 7 days or longer. Administer VOYXACT by subcutaneous injection only. Inject into the front of…
Sibeprenlimab-Szsi side effects
The following clinically significant adverse reactions are described elsewhere in the labeling: Immunosuppression and Increased Risk of Infections [see Warnings and Precautions (5.1) ] Immunosuppression and Immunization Risks [see Warnings and Precautions (5.2) ] Most common adverse reactions are upper respiratory tract infection and injection site erythema. ( 6.1 ) To report SUSPECTED ADVERSE REACTIONS, contact Otsuka America Pharmaceutical, Inc. at 1-800-438-9927 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. The safety of VOYXACT was evaluated in a randomized, double-blind, placebo-controlled, clinical study in patients with IgAN (VISIONARY). The median duration of exposure was 44 weeks in the 259 patients treated with VOYXACT and 48 weeks in the 251 patients administered placebo. The most common adverse reactions (reported in ≥10% of patients treated with VOYXACT and at a higher incidence than placebo) in patients treated with VOYXACT and placebo, respectively, were infections (49% versus 45%) and injection site reactions (24% versus 23%). The most common infection was upper…
Who shouldn’t take sibeprenlimab-szsi
VOYXACT is contraindicated in patients with serious hypersensitivity to sibeprenlimab-szsi or any of the excipients of VOYXACT. Serious hypersensitivity to sibeprenlimab-szsi or any excipients in VOYXACT. ( 4 )
Every sibeprenlimab-szsi product we track (1)
Same active ingredient — different manufacturer, form, price and FDA recall record. That last one is what our independent score measures.
Only one: Voyxact.
What people report to the FDA about sibeprenlimab-szsi
The FDA Adverse Event Reporting System (FAERS) collects reports from patients and clinicians. It holds 1 reports naming sibeprenlimab-szsi, and the FDA flagged 100% of those reports as serious. The effects reported most often — leaving out reports about overdose, misuse or the condition being treated, which dominate the raw list for common medicines:
- blindness1 reports
- cytotoxic lesions of corpus callosum1 reports
- diplopia1 reports
- headache1 reports
- idiopathic intracranial hypertension1 reports
- neck pain1 reports
- papilloedema1 reports
- vision blurred1 reports
Read these as a signal, not a rate. A report does not mean sibeprenlimab-szsi caused the effect — anyone can file one, and many describe people taking several medicines for several conditions. Crucially there is no denominator: FAERS does not record how many people took the drug, so these counts cannot be turned into “X% of patients” — a bigger number often just means a more widely used or more talked-about drug. Duplicates exist, and publicity drives reporting. For what is actually established, read the FDA label section above.
Source: openFDA drug/event (FAERS), retrieved August 4, 2026.
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Frequently asked questions
What is sibeprenlimab-szsi?
Voyxact (Sibeprenlimab-Szsi) is a medication used to treat Iga Glomerulonephritis, Proteinuria.
Can you take sibeprenlimab-szsi with other medicines?
It depends on the medicine. We check it against the FDA labels rather than guessing: our interaction checker searches each drug's own label for the other and quotes what it says, naming the section it came from. Run sibeprenlimab-szsi against whatever else you take — and remember that a label not naming a drug is not the same as that combination being safe.
What forms does sibeprenlimab-szsi come in?
Across the brands we track, sibeprenlimab-szsi is currently marketed as injectable, per the FDA's National Drug Code Directory. Each form is dosed differently — follow the label for the exact product you were prescribed.
Is there a generic sibeprenlimab-szsi?
We do not currently list a generic-labelled sibeprenlimab-szsi product. That does not always mean none exists — it means none appears under a generic name in the FDA data we track. Ask your pharmacist.
Cite this page
- APA
- pharmaranks. (2026, July 24). Sibeprenlimab-Szsi: uses, dosing, side effects & brands. https://pharmaranks.com/drugs/sibeprenlimab-szsi
- MLA
- “Sibeprenlimab-Szsi: uses, dosing, side effects & brands.” pharmaranks, 24 July 2026, https://pharmaranks.com/drugs/sibeprenlimab-szsi.
We summarise public FDA and NIH sources — for a clinical claim, cite the primary source we link to as well.
Sources: FDA openFDA drug label, National Drug Code Directory, and Enforcement (recall) database. This page reproduces public FDA data and is not medical advice. Dosing is set by your prescriber.
Read the full FDA label for sibeprenlimab-szsi on DailyMed (NIH) ↗.