Diethylcarbamazine Citrate, Oxibendazole: what the FDA reviewed for dog products
1 Freedom of Information summary from the FDA Center for Veterinary Medicine for products containing Diethylcarbamazine Citrate, Oxibendazole, as typed records: every value below is followed by the verbatim passage it was taken from. Species as stated by each summary: Dogs.
Products
- Filaribits® Plus Chewable Tablets (NADA/ANADA 136-483)
Filaribits® Plus Chewable Tablets NADA 136-483, Supplemental approval, January 18, 1989; sponsor Zoetis Inc.; species: Dogs; foi_id 414; FDA PDF
Indication
Prevention of heartworm (Dirofilaria immitis) and hookworm (Ancylostoma caninum) infection, removal and control of whipworms (Trichuris vulpis) and, per this supplement, removal and control of mature and immature intestinal Toxocara canis (ascarids) in dogs.
Dose regimen
3 mg diethylcarbamazine citrate and 2.27 mg oxibendazole per pound of body weight, oral (chewable tablet, free-choice or on food), once a day, continuous daily administration throughout the period of hookworm/mosquito exposure
FILARIBITS Plus are given orally (once a day) at a dosage rate of 3 mg diethylcarbamazine citrate and 2.27 mg oxibendazole per pound of body weight.
Target-animal safety
duration field trials averaging 73.5 days.
No adverse reactions or unusual observations associated with FILARIBITS Plus were reported by investigators conducting the critical laboratory trials. Untoward reactions in the clinical trials were minimal in number as well as severity.
| Finding | Quote |
|---|---|
| Side effects (vomiting, diarrhea, anorexia, tenesmus, depression, elevated ALP and WBC) in 4 field-trial dogs | Investigators in the clinical trials reported one or more of the following side effects in a total of 4 dogs: vomiting, diarrhea, anorexia, tenesmus and depression plus elevated serum alkaline phosphatase and white blood cell count levels. |
| Boxed warning for occasional hepatic toxicity including fatalities | Labeling contains a boxed warning that addresses the occasional association with hepatic toxicity including several fatalities. |
Effectiveness
Clinical field trials at 18 practices in 12 states in ascarid-infected dogs given FILARIBITS Plus daily (average 73.5 days); 7 pivotal investigators also ran FILARIBITS (diethylcarbamazine only) controls (11 dogs); plus four critical laboratory studies (each dog its own control) in 42 dogs; n = 68 (field trials); primary endpoint: Percent of dogs cleared of ascarids at fecal rechecks (approx. 30, 60 and 90 days); result: Field: significantly more dogs cleared with FILARIBITS Plus than FILARIBITS (Mantel-Haenszel P<0.02); pivotal T1 group 100% (31/31) cleared at rechecks 1 and 2 vs 72.7% (8/11) and 70% (7/10) for FILARIBITS controls. Laboratory: 100% ascarid removal in all four critical studies after 30 days
In the clinical (field) trials, 68 dogs from eighteen veterinary practices in twelve states were studied. All dogs were infected with ascarids when entering the study.
Adverse reactions
| Term | Treated | Control | Quote |
|---|---|---|---|
| Vomiting, diarrhea, anorexia, tenesmus, depression, elevated ALP and WBC (one or more) | 4 | Investigators in the clinical trials reported one or more of the following side effects in a total of 4 dogs: vomiting, diarrhea, anorexia, tenesmus and depression plus elevated serum alkaline phosphatase and white blood cell count levels. |
Extraction notes: 1989 Category II supplemental approval adding the ascarid claim; no new target animal safety studies (safety data unchanged, refers to original FOI summary), no PK. Target_animal_safety here records field-trial safety observations only, with no dose-multiple study. Tables VI/VII give per-investigator clearance data.
Reproduce: foi_structured_search(query="Diethylcarbamazine Citrate, Oxibendazole") and foi_summary_get(foi_id=...) in dog-geroscience-mcp; dataset foi-summaries-dog (config structured).