My dog had to stop metacam as it was affecting her kidneys. The vet suggested librela, which is a monoclonal antibody which targets NGF in the body, as reduces pain in the subject, and thus makes it easier for the dog to get around. I was keen on this, as I had been in a human trial for the same type of injection for my own arthritis 2 years ago and it did wonders. I am now waiting the approval of the drug is my own trial. Pixie received her first injection of librela on 20th May, and just like me, she had a very noticeable increase in mobility, and appeared to have much less pain. Her 2nd dose was administered on 17th June, and again the effect was a very noticeable improvement in her walking. I thought I had found the miracle to help my 14 year old dog to have a better quality of life. On 22nd June she developed a cough, which at first was thought to be kennel cough, but subsequently proved to be a cardiac cough. on 28th June she suddenly became unwilling to exercise, was panting heavily, and fainted when she tried to run towards a doggy friend. I managed to get a vet's appointment for the next day. At this stage they still though she had kennel cough, but I was suspicious that the sudden change meant something else was going on. She was given antibiotics, and sent home with me to rest. Over the next few days, her coughing, which only ever happened when she was resting, stopped, but her breathing became increasingly faster. By 4th July (a Sunday) she was refusing to eat, drinking very little, and her breathing was becoming noisy as well as fast. I stayed up with her all night. Early Monday morning (5th July) her tongue turned blue. I immediately phoned the vet, who said to take her straight to them, which took about 10 minutes. At the vets they put her straight on oxygen, while they checked her over. Her lungs and airways were clear, but she was found to be suffering an extremely bad heart arrhythmia. They put her on an IV of something to try and stop the arrhythmia, but despite their best efforts, it could not be stopped, and she remained blue. Within the hour she was euthanised to prevent further suffering, as if left she would have died in agony, because her heart was failing. She has never had any heart problems previously, and at her last health check in late March, I was told that her heart and lungs were sound, and very good for a dog of her age. However, she was beginning to show signs of the metacam affecting her kidneys, and that was stopped. Of course, I cannot be certain that librela was the cause, but she only managed 2 doses, and 18 days after the 2nd dose she was dead. I am now going to refuse to be treated with the human equivalent, when it is licensed later this year. I am sure this would be a very rare case, but I don't think it is worth the risk. I am now heartbroken, and feel like a murderer for allowing Pixie to be treated with librela.
But it is still a worthwhile thing to report these awful outcomes just in case there has been a causal link with the medication. 
