Should we have concerns with generic versus brand antimicrobial drugs? A review of issues

Abstract

Objectives To explore the issues involving generic versus brand antimicrobial drug products and provide an overview of assessments of equivalence and their potential relevance to health outcomes. Methods In April and May 2010, literature searches were performed in MEDLINE and EMBASE for studies involving antimicrobial drug products that convey equivalence or non-equivalence of generic and brand-name drugs. Key findings Sixty-six studies involving antibiotics, antifungals, antivirals and antimalarials were identified for analysis. The types of studies were categorized into microbial assays, pharmaceutical assays, bioequivalence and those that assess clinical endpoints. Studies varied markedly on equivalence measures between generic and brand drug products. Thirty-four of 66 (52%) were primarily bioequivalency studies with 30 of 34 (88%) demonstrating positive outcomes for equivalency. Two of 22 studies (9%) involved microbial and/or pharmaceutical assays for quality assurance testing and presented the largest disparity in equivalence. Ten studies compared outcomes of a clinical nature and concluded no significant difference in outcome between generic and brand products. Ten of 66 (15%) studies were published before 2000 and 11 (17%) were conducted in the USA. Conclusions In the USA, it is unlikely that use of generic antibiotics and antimicrobials pose a problem for patients with infectious diseases, where quality safeguards exist and patients are informed when generic substitution occurs. However, with expansion of international markets and questionable drug supply chains -particularly with the advent of the internet -consumers and providers should be aware of drug product quality differences that may impact patient outcomes.

The impact of South Korea’s new drug-pricing policy on market competition among off-patent drugs

“…Overall, price competition can be achieved when coordinated demand and supply-side policies are considered [8]. Care is not compromised with demonstrated bioequivalence between generics and originators [1,2,[52][53][54]. Supply-side measures such as price cutting are relatively easy to implement in Korea but the lack of demand-side measures appears insufficient to create a competitive market.…”

The prescribing of generic medicines in Nigeria: knowledge, perceptions and attitudes of physicians

“…This includes educating physicians on issues such as bioequivalence for generics to address misconceptions (2). In addition, emphasizing that the prescribing of good quality generics should not compromise care as seen by published studies across a range of disease areas (7)(8)(9)(10)(11)(12)(13).…”

“…As a result, published studies from these countries have shown similar effectiveness rates between generics and originators (brand name medicines) across a range of classes. These include medicines for infectious and cardiovascular diseases as well as mental health (7)(8)(9)(10)(11)(12)(13).…”

Pricing of oral generic cancer medicines in 25 European countries; findings and implications

“…Initiatives to enhance greater use of generic cancer medicines include encouraging international non-proprietary name (INN) prescribing, financial incentives to enhance the prescribing and dispensing of generics versus originators, as well as compulsory generic substitution (29)(30)(31)(32)(33)(34)(35)(36)(37)(38). INN prescribing is supported by multiple publications showing no difference in effectiveness and safety between generics and originators across a range of disease areas including oncology medicines (28,(39)(40)(41)(42)(43)(44). There have though been concerns with generic imatinib due to different polymorphic forms between the originator and generics as early small scale studies suggested differences (45).…”