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Attruby

acoramidis
small moleculeTransthyretin (stabiliser)Oral small-molecule transthyretin tetramer stabiliserTransthyretin amyloid cardiomyopathy (ATTR-CM) in adults
Species
RatDog
Longest study
39 wk
Genotox
Conducted Conducted
Carcinogenicity
Conducted Conducted
Repro
Conducted Conducted
First dose
Not conducted Not stated publicly

Speciesopen answer page →

Species
Rat and dog
“There were no histopathology findings consistent with kidney injury in chronic toxicology studies in two non-human species (Study 20141689, 26-week toxicity study in rats and Study 21141692, 39-week toxicity study in dogs)”
✓ VerifiedFDA integrated review, p. 92Source ↗
Why that species
PK profiles in rats and dogs comparable to humans; species appropriate for acoramidis and its metabolites
“Overall, there was no significant difference observed in PK profiles between animals and humans that would limit the interpretation of animal toxicology studies and the nonclinical species used were considered appropriate for the safety of acoramidis and its metabolites in human.”
✓ VerifiedFDA integrated review, p. 126Source ↗
Surrogate molecule
No surrogate; the clinical compound was tested
“Repeat-dose toxicity studies were conducted in rats for up to 26 weeks with oral dose levels ranging from 50 to 1000 mg/kg/day.”
✓ VerifiedFDA integrated review, p. 131Source ↗

Study lengthopen answer page →

Longest pivotal study
39 (39-week dog)
“Repeated dose toxicity studies comprised studies in rats and dogs with once daily administration of acoramidis by oral gavage during up to 26 and 39 weeks, respectively.”
✓ VerifiedEMA assessment report, p. 29Source ↗
Pivotal GLP studies
4-, 13- and 26-week rat and 4-, 13- and 39-week dog oral studies
“The pivotal repeated dose toxicity studies comprised studies of 4, 13 and 26 weeks in rats, and of 4, 13 and 39 weeks in dogs.”
✓ VerifiedEMA assessment report, p. 29Source ↗
Route in tox
Oral gavage, once daily
“Repeated dose toxicity studies comprised studies in rats and dogs with once daily administration of acoramidis by oral gavage during up to 26 and 39 weeks, respectively.”
✓ VerifiedEMA assessment report, p. 29Source ↗

Skipped studiesopen answer page →

Genotoxicity
Negative in Ames, rat micronucleus and alkaline comet assays
“Acoramidis showed no mutagenic or clastogenic activity in a standard battery of genotoxicity studies, which included a bacterial reverse-mutation study and rat micronucleus and alkaline comet assays (Table 70).”
✓ VerifiedFDA integrated review, p. 136Source ↗
Carcinogenicity
2-year rat and 26-week rasH2 mouse: no carcinogenic potential
“A two-year oral carcinogenicity study in rats did not identify any carcinogenic potential at doses up to 50 mg/kg/day (males) or 350 mg/kg/day (females), doses producing exposures that approximated the clinical AUC or were 11-times the clinical AUC, respectively, at the MRHD. No acoramidis-related tumors were observed in a 26-week oral carcinogenicity study in Tg rasH2 mice.”
✓ VerifiedFDA integrated review, p. 81Source ↗
Reproductive & developmental
Rat PPND: reduced pup weight gain and learning deficits at 1,000 mg/kg/day; no adverse effects at 350 mg/kg/day (~18x AUC)
“Decreased body weight gain from the neonatal period to weaning and learning deficits were observed in the offspring of dams given 1,000 mg/kg/day. No adverse effects on pre- and postnatal development were observed at 350 mg/kg/day, approximately 18-times the clinical exposure at the MRHD based on AUC.”
✓ VerifiedFDA integrated review, p. 118Source ↗
Safety pharmacology
hERG IC50 >50 µM (>33-fold margin over free clinical exposure); no QT effect in dog telemetry
“The reported IC50 of >50 µM represents a >33-fold margin over the free fraction of the high clinical exposure estimated at 12,300 ng/mL. A GLP dog telemetry study demonstrated no concentration QT effect at multiple plasma concentrations above the high clinical exposure estimated at 12,300 ng/mL”
✓ VerifiedEMA assessment report, p. 26Source ↗

First doseopen answer page →

First-in-human starting dose
Not stated in public reviews
Why it's blank

The public FDA and EMA reviews of Attruby don't say how the first human dose was chosen. That rationale is in the IND, which is confidential, so it is missing for most approved products.

How it's usually set for small molecules outside oncology

Find the highest dose with no adverse effects (NOAEL) in each animal species, convert it to a human equivalent dose, usually by body surface area, pick the most appropriate species, then divide by a safety factor (default 10) to get the maximum recommended starting dose.

“In general, one should consider using a safety factor of at least 10. The MRSD should be obtained by dividing the HED by the safety factor.”
✓ VerifiedFDA 2005: Estimating the Maximum Safe Starting Dose in Initial Clinical…, p. 7Source ↗
This product's starting point

NOAEL / key findings: Rat 26-week NOAEL 50 mg/kg/day (males, body weight loss) and 600 mg/kg/day (females) (FDA integrated review, p. 131)

Full method, every step sourced →

NOAEL / key findings
Rat 26-week NOAEL 50 mg/kg/day (males, body weight loss) and 600 mg/kg/day (females)
“The no observed adverse effect level (NOAEL) was determined to be 50 mg/kg/day in male rats based on significant body weight reductions (>10%), and 600 mg/kg/day in female rats”
✓ VerifiedFDA integrated review, p. 131Source ↗

Risksopen answer page →

Immune & cytokine safety
Not stated in public reviews
Not reported in the public reviews. Reviewers summarise selectively, so this usually means it wasn't discussed publicly, not that it wasn't studied.
Biodistribution & persistence
No tissue accumulation or retention; no selective association with melanin-containing tissues in pigmented rats
“Overall, there was no accumulation or retention of radioactivity in tissues. The data also suggested that [14C]acoramidis derived radioactivity did not selectively associate with melanin containing tissues in the pigmented rat.”
✓ VerifiedEMA assessment report, p. 27Source ↗
Modality-specific risk
Spatial learning deficits in offspring of rats given 350 or 1000 mg/kg/day
“In the water-maze test performed on PND 63 acoramidis-related effects on proximal and spatial learning deficits were noted for pups from animals administered 350 or 1000 mg/kg/day.”
✓ VerifiedEMA assessment report, p. 36Source ↗

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