Reported Reactions

Drugs

Brand name · Belumosudil

Rezurock: adverse event reports filed with FDA

2,378 reports list it as a suspect or interacting product, 2021–2026.

2,378
reports as suspect product
0% of all reports · about 501 a year
590
reports, 12 months to June 2026
642 in the 12 months before
47.8%
marked serious by the reporter
57.4% across all reports
8.1%
record death among outcomes, as reported
193 reports · not verified by FDA

2,378 adverse event reports received by FDA list the brand name Rezurock (belumosudil) as a suspect or interacting product, from October 2021 to June 2026. A further 245 reports list it only as a concomitant medication, and those are not counted in the figures on this page.

In the 12 months to June 2026, 590 reports listed it, close to the 642 of the 12 months before. FDA releases FAERS data quarterly, so the newest months are incomplete and grow in later releases. Over its reporting history that is about 501 reports a year and 0% of the 20,646,523 reports in the database. How many people take it is not in the data, so a count is not a rate of occurrence.

The MedDRA terms listed most often are product use in unapproved indication (19%), inappropriate schedule of product administration (18.5%) and fatigue (8.9%). A report can list several reactions, so shares add to more than 100%; 400 different terms appear across these reports. Product use in unapproved indication is recorded in 19% of these reports, against 1.2% of all reports in the database.

47.8% of the reports are marked serious by the reporter; 8.1% record death among the outcomes and 26.9% record hospitalisation, as reported. 48.1% of the reports came from consumers, and the largest patient age group is 45 to 64 (27.4%). FDA states that "a causal relationship cannot be established between product and reactions listed in a report" and that for any given report "there is no certainty that a suspected drug caused the event."

Reports by month, five years

069137Jul 2021: 0Aug 2021: 0Sep 2021: 0Oct 2021: 1Nov 2021: 39Dec 2021: 152022Jan 2022: 15Feb 2022: 137Mar 2022: 21Apr 2022: 10May 2022: 92Jun 2022: 14Jul 2022: 19Aug 2022: 103Sep 2022: 1Oct 2022: 74Nov 2022: 55Dec 2022: 32023Jan 2023: 3Feb 2023: 4Mar 2023: 4Apr 2023: 9May 2023: 6Jun 2023: 10Jul 2023: 11Aug 2023: 31Sep 2023: 40Oct 2023: 29Nov 2023: 32Dec 2023: 382024Jan 2024: 52Feb 2024: 70Mar 2024: 51Apr 2024: 50May 2024: 52Jun 2024: 55Jul 2024: 61Aug 2024: 46Sep 2024: 43Oct 2024: 48Nov 2024: 68Dec 2024: 472025Jan 2025: 68Feb 2025: 45Mar 2025: 66Apr 2025: 37May 2025: 56Jun 2025: 57Jul 2025: 51Aug 2025: 32Sep 2025: 58Oct 2025: 53Nov 2025: 44Dec 2025: 332026Jan 2026: 73Feb 2026: 60Mar 2026: 31Apr 2026: 57May 2026: 57Jun 2026: 41

Reports by the month FDA received them. FDA releases FAERS data quarterly, so the newest months are incomplete and grow in later releases.

By year received

03226432021: 5520212022: 54420222023: 21720232024: 64320242025: 60020252026: 3192026

2026 covers reports received through June 2026 only.

Reactions recorded in the reports

share of Rezurock reports recording the termall reports in the database

  1. Product use in unapproved indicationused for a purpose not on the label19%451
  2. Inappropriate schedule of product administrationthe product was taken at the wrong times18.5%439
  3. Fatiguetiredness8.9%212
  4. Hospitalisationadmission to hospital6%142
  5. Diarrhoealoose or frequent stools5.3%125
  6. Nauseafeeling sick5.2%124
  7. Pneumonialung infection5.2%123
  8. Deaththe patient died; cause not stated by this term5%118
  9. Drug ineffectivethe medicine did not work as expected4.5%108
  10. Product dose omission issuea dose was missed4.5%107
  11. Condition aggravatedthe condition being treated got worse4.2%101
  12. Dyspnoeashortness of breath4.1%97
  13. Off label useused for a purpose or in a way not on the label3.9%92
  14. Coughcough3.4%82
  15. Painpain, site not specified3.4%81
  16. Astheniaweakness or lack of energy3.1%74
  17. Headachehead pain2.9%70
  18. Arthralgiajoint pain2.5%59
  19. Rashskin rash2.5%59
  20. Nasopharyngitisa cold2.4%58
  21. Covid-19COVID-19 infection2.4%57
  22. Muscle spasmsmuscle cramps2.4%57
  23. Decreased appetitereduced appetite2.3%55
  24. Falla fall2.1%51
  25. Influenzaflu2.1%49
  26. Vomitingbeing sick2%48
  27. Pruritusitching2%47
  28. Dry eyedry eye1.9%45
  29. Dizzinesslight-headedness or unsteadiness1.7%41
  30. Disease progressionthe disease advanced1.7%40

Top 30 of 400 MedDRA preferred terms recorded across these reports, with a plain-language gloss where one is available. One report can record several terms. The hollow bar is the share of all reports in the database; it describes the reports, not the patients. FDA states that adverse event reports "represent a small percentage of total usage numbers of a product", that "common products may have a higher number of adverse events due to the higher total number of people using the product", and that the data "by themselves are not an indicator of the safety profile of the drug or biologic."

Outcomes recorded

Death8.1%193
Life-threatening0.9%21
Hospitalisation (initial or prolonged)26.9%640
Disability0.4%9
Congenital anomaly0%0
Other serious33%784
Not serious52.2%1,242

Outcome flags as the reporter set them; a report can carry several, and "other serious" is FDA's own category for serious reports outside the named outcomes. Grey bar: all 20,646,523 reports. FDA has not verified any outcome and states that the reports "cannot be used to estimate the incidence of these events."

Patients and reporters

Patient age

Under 20.1%2
2 to 111.7%40
12 to 172.6%61
18 to 4414.9%354
45 to 6427.4%651
65 to 7419.9%474
75 and over4.8%113
Age not given28.7%683

Patient sex

Female42.7%1,016
Male47.4%1,126
Not given9.9%236

Who reported

Physician41.3%983
Pharmacist2.4%58
Other health professional8%191
Lawyer0%0
Consumer or non-health professional48.1%1,144
Not given0.1%2

Age and sex as stated in the report; the reporter's qualification is the primary source recorded by FDA. 92% of reports give the United States as the country of the event or reporter.

Reason for use recorded

Indication as recorded (MedDRA)ReportsShare
Chronic graft versus host disease90638.1%
Graft versus host disease56223.6%
Acute myeloid leukaemia1265.3%
Acute graft versus host disease421.8%
Acute lymphocytic leukaemia371.6%
Myelodysplastic syndrome331.4%

The indication field is filled in by the reporter and is often blank; shares are of all 2,378 reports.

In context

MeasureRezurockAll reports
Reports as suspect product2,37820,646,523
Share of that pool—0%
Reports, latest 12 months5901,332,454
Marked serious47.8%57.4%
Death recorded among outcomes, per 1,000 reports8191
Hospitalisation recorded, per 1,000 reports269213
Consumer-filed share48.1%45.8%
Top term, share of reportsProduct use in unapproved indication 19%1.2%

Shares are of reports, not of patients treated. The number of people taking a product is not in the data, so none of these figures is a rate, and differences between columns reflect who takes a product, who reports and how long it has been sold. FDA states that adverse event reports "represent a small percentage of total usage numbers of a product", that "common products may have a higher number of adverse events due to the higher total number of people using the product", and that the data "by themselves are not an indicator of the safety profile of the drug or biologic."

Questions about Rezurock reports

How many adverse event reports has FDA received for Rezurock?

2,378 reports list Rezurock as a suspect or interacting product in the openFDA FAERS release of 28 Sep 2026, covering reports received through June 2026. 590 of them arrived in the latest 12 months. Another 245 list it only as a concomitant medication.

What reactions are recorded in Rezurock reports?

product use in unapproved indication (19%), inappropriate schedule of product administration (18.5%), fatigue (8.9%), hospitalisation (6%) and diarrhoea (5.3%). These are MedDRA preferred terms coded from what the reporter described; a report can list several, and a term's presence is not a finding that Rezurock was responsible.

How serious are the reports?

47.8% are marked serious by the reporter. Among the outcomes recorded, 8.1% of reports include death and 26.9% include hospitalisation. FDA has not verified these outcomes and states that the reports "cannot be used to estimate the incidence" of the events.

Who files these reports?

consumer or non-health professional (48.1%), physician (41.3%) and other health professional (8%). Most reports reach FDA through the manufacturer, which must forward reports it receives.

Are reports for Rezurock rising?

590 reports in the 12 months to June 2026, close to the 642 of the 12 months before. FDA releases FAERS data quarterly, so the newest months are incomplete and grow in later releases. Counts also move with how many people take a product, its time on the market and publicity.

Do these reports show that Rezurock was responsible for these reactions?

No. FDA states that "a causal relationship cannot be established between product and reactions listed in a report" and that for any given report "there is no certainty that a suspected drug caused the event." The reaction may relate to the condition being treated, to other medicines, or to something else.

Is this a list of the side effects of Rezurock?

No. It is a count of what was reported to FDA. The adverse reactions observed in clinical studies are printed on the FDA-approved label, which a pharmacist or clinician can go through with you.

How do I report an adverse event?

Consumers and health professionals can report to FDA through MedWatch (Form FDA 3500 online, or 1-800-FDA-1088), or to the manufacturer, which must pass reports on. See the guide on how to report.

Where this comes from. Counts are built from the openFDA Drug Adverse Event (FAERS) bulk export released 28 Sep 2026, which holds reports FDA received through 30 Jun 2026. Drug names are as reported, resolved to the brand or generic name on the FDA label where openFDA's harmonisation matched them; classes are the pharmacologic class (EPC) from the label and the National Drug Code Directory of 17 Sep 2026. A report counts here when it lists Rezurock as a suspect or interacting product; reports listing it only as a concomitant medication (245) are excluded. No report narrative, lot number, patient detail or reporter identity is published. See the methodology and sources; FDA's record is authoritative, and corrections are handled within five working days.

Drug data (FAERS) through 30 Jun 2026; device data (MAUDE) through 31 Aug 2026. Not medical advice.