Discrepancy between theory and reality of treatment of ophthalmological patients due to the availability of medication and lawful aspects using the example of cats
In Germany the application, dispensing or prescription of pharmaceuticals is regulated by law through the AMG and TÄHAV. These regulations stipulate that medicinal products used for the treatment of animals are licensed for the animal species and therapeutic target area. Only in case of a therapeutic emergency in therapy extra-label drug use or preparation of medicinal products is possible according to § 56a of the AMG. A therapeutic emergency exists if there is no medicine is available for the treatment of individual cases, which is approved for the animal species or the specific therapeutic target area, and the medical care of the animal is otherwise seriously endangered. Only a few approved drugs are available in veterinary ophthalmology. As a result, human medicinal products often have to be used. A revised form of the TÄHAV has been in force since 01.03.2018. This form further regulates and limits the use of antibiotics. This applies, among other things, to the application in cats.
The aim of this dissertation was to collect data on the occurrence and frequency of feline eye diseases and to show the frequency of extra-label drug use for these diseases. Based on a literature research, theoretical treatment schemes (“lege artis”) were generated for 26 selected diseases. These were then examined and discussed with a view due to their feasibility based on the availability of medicinal products and lawful aspects in Germany.
Examination data were evaluated from 876 cats of the Department of Ophthalmology of the „Small Animal Clinic“ of Freie Universität Berlin and the „Kleintierpraxis am Aischbach” in Gerlingen (Baden-Württemberg) as a basis for clinical data. The data were collected between 01.01.2015 and 31.12.2018. 1198 examination results were observed from 925 ophthalmic examinations. The most common diseases include conjunctivitis, keratitis, uveitis, hypertensive retinopathy and glaucoma. 78.1% (n = 722) of these cases would have required therapy.
During the study period (01.01.2015 – 31.12.2018), eight ophthalmic veterinary drugs, approved for cats, were available for therapeutic purposes.
In order to treat the sample population lege artis extra-label drug use and / or preparation of medicinal products would have been determined in 68.8 % (n = 497) of the cases. In 96.8 % (n=481) this would have been an extra-label drug use of pharmaceuticals for human medicine. Diseases such as a retrobulbar process, tear film instability or keratoconjunctivitis sicca (KCS), infection of the conjunctiva with chlamydia and / or mycoplasma, erosion and ulcer of the cornea as well as a hypertensive retinopathy can be optimally treated in Germany based on the availability of pharmaceuticals and the statutory framework. In these cases, the extra-label drug use of veterinary and / or human medicine medicinal products can be reasonably justified with the therapeutic emergency according to § 56a of the AMG.
Mydriatics, antivirals and drugs for the therapy of feline glaucoma were not approved for veterinary medicine during the study period. The extra-label drug use of these drugs was therefore essential. For the medically correct care more than 60 % of the cases of the common diseases, such as keratoconjunctivitis, uveitis or glaucoma, extra-label drug use had to be occurred. In contrast, only 27.1 % of patients with hypertensive retinopathy would have had to be treated with unapproved drugs.
The results show limitations in the implementation of therapy for feline ophthalmologic diseases in Germany. On the one hand, this is related to legal regulations. On the other hand, this is also due to the lack of availability of efficacious drugs. This gap could be closed by extensive approvals of ophthalmic veterinary drugs concerning the animal species and the area of application as well as by the development and research of new active agents and veterinary medicinal products, in particular for the topic therapy of the feline eye.