Pets
“The injectable heartworm preventive ProHeart (ProHeart 6 and ProHeart 12), which contains moxidectin, carries a company-provided warning handout listing potential side effects including death." (Surrounding post: "when the first ProHeart 6 came out about 15 years ago, it was a drug that actually did get pulled off the market... Weirdly,…”
Plain restatementProHeart 6 and ProHeart 12 (moxidectin, extended-release injectable for dogs) are supplied with a Client Information Sheet for the dog owner, and that sheet lists death among possible outcomes of adverse reactions.
General information only - not veterinary advice.
The specific claim checks out. The FDA-approved labeling for ProHeart 6 and ProHeart 12, injectable moxidectin heartworm preventives for dogs, tells the veterinarian to give the owner a Client Information Sheet made by the manufacturer, and that sheet does say that in some cases the listed side effects can be serious and can cause death. What the rest of the clip says about the history is not supported. ProHeart 6 was voluntarily recalled in September 2004, about 22 years ago rather than 15, and it did not come back unchanged in 2008: FDA records say the manufacturing process was altered after studies pointed to residual solvents, and the return was conditioned on restricted distribution, mandatory veterinarian training and certification, an age limit, lot recording and adverse event reporting, with the owner handout being one part of that plan rather than the only change. The labeling itself states that adverse event reports are incomplete and that it is not always possible to establish that the drug caused what was reported, so the death listing is not a measured risk figure. The approved labeling also says dogs should be tested for existing heartworm infection before the injection is given and that owners should be told what signs to watch for. Questions about heartworm prevention for a particular dog belong with a veterinarian, who can weigh the drug's labeling against the risk of the disease. General information only, not veterinary advice.
[drifted from the evidence:] The injectable heartworm preventive ProHeart [drifted from the evidence:] (ProHeart 6 and ProHeart 12), [drifted from the evidence:] which contains moxidectin, [drifted from the evidence:] carries a company-provided warning handout listing potential side effects including death." (Surrounding post: "when the first ProHeart 6 came out about 15 years ago, it was a drug that actually did get pulled off the market... Weirdly, a [drifted from the evidence:] couple years later, it came back on the market unchanged. The only change was FDA said to veterinarians... you must give the client [drifted from the evidence:] the handout from the [drifted from the evidence:] company that [drifted from the evidence:] says these are the potential side effects, which include death.")
ProHeart 6 and ProHeart 12 (moxidectin, [added by the neutral restatement:] extended-release injectable for dogs) are supplied with a Client [added by the neutral restatement:] Information Sheet for the [added by the neutral restatement:] dog owner, and that [added by the neutral restatement:] sheet lists death [added by the neutral restatement:] among possible outcomes of adverse reactions.
Red-tinted words in the claim drifted from the evidence. Green-tinted words are what a neutral restatement needs.
The trace / claim to source
- ProHeart 6 and ProHeart 12 contain moxidectin and are extended-release injectables for dogs, labeled for 6 and 12 months of heartworm prevention respectively.
- The approved labeling for both products directs the veterinarian to provide the owner with a Client Information Sheet and to review it before administering. The sheet is produced by the sponsor, Zoetis, and is attached to the package insert.
- Those owner sheets do state death as a possible outcome: the ProHeart 6 sheet says the listed side effects may in some cases be serious and may cause death; the ProHeart 12 sheet says death has in some cases been reported as an outcome of the listed adverse events.
- Seizures appear in the labeling: in ProHeart 6 field studies and in post-approval neurological reports, and in the ProHeart 12 field study table.
- ProHeart 6 was voluntarily recalled in September 2004 at FDA CVM's request over reports of serious adverse events, and it did return to the US market in 2008.
- The post says the product "came back on the market unchanged" and that "the only change" was the owner handout. The FDA record and contemporaneous reporting say otherwise: the manufacturing process was altered after studies pointed to residual solvents, and the 2008 return was conditioned on restricted distribution, mandatory veterinarian training and certification, a restriction to healthy dogs aged 6 months to 7 years, lot-number recording, mandatory adverse event reporting and, at that time, signed owner consent. The handout was one element of a larger risk minimization plan, not the sole change.
- The post dates the original ProHeart 6 launch and withdrawal to "about 15 years ago." The withdrawal was September 2004, about 22 years before the post.
- "The side effects include death" is presented as a distinguishing alarm about this product. A death statement in labeling reflects what has been reported in post-approval surveillance and is common across veterinary and human injectable products; the label itself says not all adverse reactions are reported to FDA CVM and that it is not always possible to estimate frequency or establish a causal relationship from such reports. Reading a passive-surveillance listing as a measured risk rate is causal overreach.
- "Tons of seizures" is stated without a rate or a comparator. In the ProHeart 12 registration field study, seizures were recorded in 3.4% of ProHeart 12 dogs versus 2.4% of dogs on an oral control over 605 days, a difference the study was not designed or powered to resolve.
- The segment frames a veterinarian-administered, FDA-approved preventive as something to avoid without stating what the condition being prevented requires. Discouraging a prevention product on adverse event listing alone, with no comparison to the risk of the disease, is care substitution in effect.
- The true incidence of serious adverse events, including death, attributable to moxidectin injectables cannot be established from the post-approval reports, because reporting is voluntary and incomplete and causation is not assessed in those listings. The labeling says this explicitly.
- Whether the RiskMAP or the Client Information Sheet requirement has been amended since the July 2, 2019 version could not be confirmed from any document found; the status above is stated as of that document.
- Whether the seizure signal in the ProHeart 12 field study reflects a real difference from oral macrocyclic lactones is not resolved by that study.
The approved labeling for both products instructs: always provide the Client Information Sheet and review it with owners before administering, and advise the owner to observe the dog for adverse drug events including those described on the sheet. The sheet is attached to the package insert and is posted online by the sponsor for reprinting. The owner-facing sheets do state death. The ProHeart 6 client sheet, listing signs of a severe allergic reaction and other possible side effects, says that in some cases these side effects may be serious and may cause death. The ProHeart 12 client sheet says that in some cases death has been reported as an outcome of the adverse events listed. The professional label carries the same point in the WARNINGS section: anaphylactic and anaphylactoid reactions may occur in some dogs following administration alone or with vaccines, and in some cases these reactions have resulted in death following administration of moxidectin microspheres. The ProHeart 6 label also states that in some cases anaphylactic reactions have resulted in liver disease and death. Post-approval adverse event listings for ProHeart 6 include neurological events such as seizures. On the history: FDA CVM raised safety concerns and Fort Dodge Animal Health voluntarily recalled ProHeart 6 in September 2004. Events of concern to CVM included anaphylaxis, liver disease, autoimmune hemolytic disease and seizures. The product returned in June 2008 on a restricted basis. Per FDA and contemporaneous reporting, additional toxicologic and pharmacologic studies suggested residual solvents used in manufacture could have contributed to reactions, and the manufacturing process was altered; the return was conditioned on a Risk Minimization Action Plan with restricted distribution, mandatory veterinarian training and certification, a restriction to healthy dogs aged 6 months to 7 years, the client information sheet, signed owner consent, lot-number recording and adverse event reporting. In August 2013 the RiskMAP was eased: the age cap was lifted, trained technicians could administer, and signed client consent was no longer required. The current RiskMAP document covering both products is dated July 2, 2019, the date ProHeart 12 was approved; restricted distribution to RiskMAP-certified veterinarians remains stated on the labeling. In the ProHeart 12 field study (605 days), seizures were recorded in 10 of 297 ProHeart 12 dogs (3.4%) and 7 of 296 dogs (2.4%) on the oral active control; anaphylactoid/hypersensitivity reactions in 6 (2.0%) versus 4 (1.4%).
Complete reasoning
The reply is formatted for pasting into the thread where the claim is circulating.