Are there potential problems with generic substitution of antiepileptic drugs?

Abstract

In response to increasing cost pressures, healthcare systems are encouraging the use of generic medicines. This review explores potential problems with generic substitution of antiepileptic drugs (AEDs). A broad search strategy identified approximately 70 relevant articles. Potential problems with generic substitution included: The limited evidence (mainly case reports with some pharmacokinetic studies) appears to support these concerns for older AEDs. As a result, restrictions on use of specific generic AEDs are in place in some countries and recommended by some lay epilepsy organisations. As more AEDs lose patent protection, it is important to examine the question of whether generic substitution may pose problems for patients with epilepsy, and whether there should be safeguards to ensure that both physician and patient are informed when generic substitution occurs.

Pharmacotherapy in pediatric epilepsy: from trial and error to rational drug and dose selection – a long way to go

“…Although the pharmacologically active substance is the same, and bioequivalence studies should provide evidence for similar exposure to the drug, different formulations have been introduced, which are intended to modify drug release profile and as such can lead to faster or slower absorption possibly resulting in different peak concentrations [69] and consequently in a different safety profile [70]. This issue can be compounded by small differences in the bioavailability (fraction of the dose that is absorbed and reaches the systemic circulation) of AEDs ( Figure 3) [71].…”

Considerações e recomendações para o uso de formulações de drogas antiepilépticas

“…7 Há relatos de preocupação pela substituição por genéricos. 8,9,10 Relatos de casos e de séries indicam falha terapêutica depois da mudança para genéricos.…”

Patent Breadth in an International Setting

“…We do this on the basis that in practice the number of …rms capable of duplicating a product from the information available in a patent …ling may be limited. 6 Also, the presence of large marketing costs may give …rms with existing brand names a signi…cant advantage over new entrants, even though the products are very similar. 7 Finally, we treat the patent length as exogenously given.…”

“…Interestingly, we also show that harmonization of patent breadth would reduce world welfare in the North-South case. 6 Bond and Saggi (2014) note that in a number of cases where compulsory licenses have been issued for patented drugs, the licensees have struggled to produce products of acceptable quality. 7 This holds for the case of over-the-counter pain relief products, where brand name products continue to hold signi…cant market shares even though patents have expired and the production processes are well known.…”