Case Fatality Rate Analysis: Librela® vs Zorbium® Safety Response
Librela® Class Action Dismissed: Why Pet Drug Lawsuits Fail
In an unpublished opinion, a federal district court in New Jersey dismissed a class action lawsuit brought by 8 pet owners against Zoetis over allegations that the company misrepresented the safety of Librela® (bedinvetmab injection), a monoclonal antibody treatment for osteoarthritis pain in dogs. This dismissal reveals critical barriers to legal accountability in veterinary pharmaceuticals—barriers that make a Zorbium® lawsuit virtually impossible.
The Librela® Case: Everything Going Right Still Wasn’t Enough
The Librela® plaintiffs had significant advantages:
- 10,000+ adverse event reports to FDA
- FDA investigation and safety alert issued (December 2024)
- Required label updates based on post-approval safety data
- 8 organized plaintiffs with documented harm and veterinary expenses
- Similar adverse events across multiple dogs (neurological injuries, death)
Despite all of this, the court dismissed the case.
Why the Court Dismissed the Lawsuit
The court identified fatal flaws in the lawsuit that apply to virtually all pet drug cases:
1. The Learned Intermediary Doctrine The court ruled that drug manufacturers only have a duty to warn veterinarians, not pet owners directly. As long as Zoetis provided warnings to veterinary professionals, they satisfied their legal duty—even if individual pet owners never saw those warnings or weren’t adequately informed by their veterinarians.
2. FDA-Approved Warnings Presumed Adequate Under New Jersey Products Liability Act, FDA-approved warnings are presumed adequate unless plaintiffs can prove the manufacturer deliberately concealed or withheld post-approval risk information. The fact that Zoetis updated the label in 2025 actually worked against the plaintiffs—it showed the company was disclosing newly discovered risks, not hiding them.
3. No Specific Misrepresentation Identified Plaintiffs couldn’t point to specific false statements they personally saw and relied on. Generic claims that they “believed the drug was safe” were deemed too vague. Each plaintiff needed to identify exactly what Zoetis said, where they saw it, and how it influenced their decision.
4. Failed to Prove Design Defect To win on design defect theory, plaintiffs must:
- Identify a feasible safer alternative design
- Show that alternative would have received FDA approval
- Prove the drug’s risks outweigh its benefits
The court found plaintiffs failed on all three elements.
5. Federal Preemption Issues Once FDA approves a drug, federal law prohibits manufacturers from unilaterally changing the formulation. This creates a catch-22: plaintiffs must prove a safer design exists, but manufacturers can’t implement design changes without FDA approval.
Why This Makes a Zorbium® Lawsuit Nearly Impossible
If Librela®—with FDA investigation, safety alerts, and 10,000+ reports—couldn’t survive a motion to dismiss, Zorbium® faces insurmountable obstacles:
| Legal Requirement | Librela® (Dismissed) | Zorbium® (No Lawsuit) |
| FDA Investigation | ✓ Completed | ✗ None |
| Safety Communications | ✓ Issued | ✗ None |
| Required Label Updates | ✓ Mandated | ✗ None |
| Proof of Concealment | ✗ Failed | Even less evidence |
| Organized Plaintiffs | ✓ 8 people | ✗ None |
| Court Outcome | DISMISSED | Won’t even file |
The Zorbium® Reality:
- Elanco provides warnings to veterinarians (learned intermediary satisfied)
- FDA approved Zorbium® and its warnings (presumption of adequacy)
- No evidence Elanco concealed post-approval data (they report adverse events to FDA as required)
- Difficult to prove a “safer alternative” exists for post-surgical pain management
- Would need to prove risks outweigh benefits (challenging for a pain medication)
- No FDA investigation to point to as evidence of problems
What Actually Survives: Economic Harm, Not Safety Claims
The contrast is stark:
Product Safety Lawsuits → Dismissed
- Librela®: 10,000+ adverse events, FDA action → Dismissed
- Individual pet deaths → Insufficient damages, can’t prove causation
Economic Harm Lawsuits → Proceed
- Elanco’s Advantix® price-fixing case → Survived dismissal (October 2025)
- Financial harm to consumers → Sufficient damages
- Easier to prove than individual product liability
Elanco’s Financial Pressure
The context matters. As of Q3 2024, Elanco faces significant financial challenges:
- Debt-to-equity ratio of 55.8%
- Failing multiple financial health criteria
- Total debt of $3.88 billion
- Under pressure to maintain revenue streams
This financial stress provides context for why Elanco:
- Has not voluntarily paused Zorbium® sales despite over 300+ cat deaths
- Continues marketing without enhanced warnings beyond what FDA requires
- Obtained FDA Emergency Use Authorization for New World Screwworm treatment in November 2025 (for a parasite not present in the U.S.) while Zorbium® remains on market with documented deaths
The priority is clear: FDA fast-tracks approval for hypothetical threats while actual, documented deaths continue without investigation.
The Broken System Revealed
The Librela® dismissal exposes a system with no accountability for veterinary drug safety:
- Manufacturers satisfy legal duty by warning veterinarians—pet owners’ lack of knowledge is irrelevant
- FDA approval creates presumption of safety—even when thousands of adverse events occur
- Legal barriers make lawsuits unwinnable—even with FDA investigation and safety alerts
- Individual damages too small—veterinary expenses insufficient to overcome legal hurdles
- FDA acts inconsistently—investigates some drugs (Librela® 12.6% fatality) but not others (Zorbium® 9.3% cats, 50% dogs) NOT APPROVED FOR DOGS
What This Means for Zorbium® Victims
The legal dismissal of the Librela® case confirms what we’ve stated from the beginning: there isn’t enough money, nor loss, to warrant a lawyer taking these cases.
Even with:
- Thousands of adverse event reports
- FDA investigation and safety alerts
- Multiple organized plaintiffs
- Documented veterinary expenses and harm
…the lawsuit still failed.
Zorbium® has none of these advantages. No FDA investigation. No safety alerts. No organized plaintiffs. No chance of legal success under current law.
This is why documentation, FOIA requests, data analysis, and public awareness remain the only viable paths to accountability. The legal system, as currently structured, cannot provide justice for pets harmed by FDA-approved drugs.
Congressional Action Required
The Librela® dismissal demonstrates that current laws are insufficient to protect animals or provide recourse to pet owners. The combination of:
- FDA’s inconsistent enforcement (acts on Librela®, ignores Zorbium®)
- Learned intermediary doctrine (manufacturers only warn vets, not owners)
- Presumption of adequacy for FDA-approved warnings
- Insufficient individual damages to sustain litigation
…creates a system where dangerous drugs remain on the market with no accountability mechanism.
Congress must address:
- Why FDA investigates some drugs but not others with comparable or worse safety profiles
- Whether the learned intermediary doctrine adequately protects pet owners
- How to create meaningful accountability when legal remedies fail
- Whether financial pressures on manufacturers influence safety decisions
Sources:
- Federal District Court of New Jersey unpublished opinion (Librela® class action dismissal)
- Elanco Q3 2024 10-Q filing (SEC)
- FDA adverse event database
- FDA Dear Veterinarian Letter (December 2024)
- DVM360 legal analysis
Last Updated: November 2025
FDA Regulatory
Librela® (bedinvetmab)
Species: Dogs (Approved)
Indication: Osteoarthritis pain control
Approval: May 5, 2023
Manufacturer: Zoetis
12.6% Case Fatality Rate
(458 deaths / 3,674 adverse event reports)
✓ FDA TOOK ACTION
Full investigation & safety alert issued
Zorbium® (buprenorphine)
Species: Cats (Approved for post operative pain) / Dogs (Off-label)
Indication: Post-surgical pain (cats only)
Approval: January 20, 2022
Manufacturer: Elanco
9.3% Cat Case Fatality Rate
50% Dog Case Fatality Rate
✗ FDA NO ACTION
No investigation, no alerts, no response
The Regulatory Crisis
FDA investigated Librela® for a 12.6% case fatality rate but has yet to investigate:
- Zorbium® cats: 9.3% case fatality rate in the approved species
- Zorbium® dogs: 50% case fatality rate in off-label use
This means Zorbium® is killing cats at nearly the same rate that triggered Librela®’s investigation, and killing dogs at more than double the rate, yet FDA takes action for one but not the other.
FDA Safety Protocol Comparison
| Safety Protocol | Librela® (12.6%) | Zorbium® Cats (9.3%) | Zorbium® Dogs (50%) |
|---|---|---|---|
| Statistical Analysis | ✓ COMPLETED | ✗ NO ACTION | ✗ NO ACTION |
| Case Series Evaluation | ✓ COMPLETED | ✗ NO ACTION | ✗ NO ACTION |
| Safety Communication | ✓ ISSUED | ✗ NOT ISSUED | ✗ NOT ISSUED |
| Label Updates | ✓ MANDATED | ✗ NO ACTION | ✗ NO ACTION |
| Death Disclosure | ✓ REQUIRED | ✗ NO ACTION | ✗ NO ACTION |
The Primary Victims: Cats
300+ cats (and dogs, not approved for dogs) have died from the drug specifically designed to help them. These cats received Zorbium® mostly off/extra label and some for its approved indication – post-surgical pain management – yet FDA has not:
- Conducted any safety analysis despite 9.3% overall case fatality rate (including 50% fatality rate in dogs)
- Issued any safety communications to veterinarians
- Required any label updates or death disclosures
- Mandated any owner notification requirements
Meanwhile, FDA thoroughly investigated Librela® for a similar 12.6% case fatality rate in dogs.
Two years later Elanco is still telling poor pet parents their reps need to be doing a better job and explaining safety issues. Two years later veterinarians are still telling pet parents that they are unaware of any deaths!
Congressional Action Needed
This regulatory double standard demands immediate congressional oversight. FDA has the tools and authority to investigate veterinary drug safety concerns, yet selectively applies them.
Key Questions for FDA:
- If 12.6% case fatality rate triggers investigation for Librela®, why doesn’t 9.3% trigger action for Zorbium® cats.
- Why is there no response to 50% case fatality rate in off-label dog use?
- What scientific justification exists for these different investigative thresholds?
Official Sources & Documentation
- FDA Dear Veterinarian Letter – Librela® (December 2024)
- FDA Librela® Adverse Event Analysis Report
- FDA Zorbium® Approval Announcement
- FDA Animal & Veterinary Adverse Event Database
Last Updated: June 2025
Data Sources: FDA adverse event reports, official FDA communications
Note: Case fatality rates represent deaths among reported adverse events
