The Role of Prescribing Generic (Non-proprietary) Drugs in the Prevalence of Therapeutic Inertia in Multiple Sclerosis Care

Abstract

Importance: The prescription of generic (non-proprietary) compared to brand-name drugs is increasing worldwide. In many developing and emerging countries, generics companies market products at similar costs as brand-name competitors benefiting from more flexible compliance rules and regulations for marketing their products in the health system. Together, this phenomenon may influence prescriber's behavior (e.g., maintaining the same treatment despite guideline's recommendations or despite evidence of disease progression).Objectives: To compare the prevalence of therapeutic inertia (TI) between primary prescription of brand-name vs. generic drugs in the management of MS in Argentina.Design: We conducted a population-based online study comprising 117 neurologists with expertise in MS. Participants answered questions regarding their clinical practice, most commonly prescribed disease modifying agents, and therapeutic choices of 10 simulated case-scenarios that assessed TI. Inertia was defined as the lack of treatment initiation or escalation despite evidence of clinical and radiological activity (8 case-scenarios, 720 individual responses). We created the generic-brand name score (GBS) according to the 5 most frequently prescribed generic (n = 16) vs. brand-name (n = 9) drugs for MS, where scores higher than 1 indicated higher prescription of generic drugs and scores lower than 1 indicated higher prescription of brand-name agents. Candidate predictors of prescribing generic drugs included demographic data, MS specialist vs. general neurologist, practice setting, years of practice, volume of MS patients, risk preferences, costs of annual treatment.Participants and setting: population-based prospective study using including neurologists who care for patients with multiple sclerosis across Argentina.Exposure: prescription of generic vs. brand-name MS drugsMain outcome of interest: Therapeutic inertia (TI), defined as lack of treatment escalation when goals are unmet. Secondary outcomes included factors associated with generic drug prescription and costs of MS treatment.Results: Ninety participants completed the study (completion rate 76.9%). TI was observed in 153 (21.3%) of participants' responses. The evaluation of aggregate responses revealed a mean GBS score (SD) of 3.44 (2.1), with 46 (51.1%) participants having a GBS equal to or higher than 1. Older age (OR 1.19; 95% CI 1.00–1.42), being a general neurologist (OR 3.91; 95% CI 1.19–12.8), and being more willing to take risks in multiple domains (SOEP score OR 1.06, 95% CI 1.01–1.12) were associated with higher prescription of generic drugs in MS care. Costs of treatment were not associated with prescribing generic drugs. There was no difference in the annual costs of MS treatment for primary prescribers of brand-name vs. generic drugs (67,500 US$ vs. 67,496 US$; p = 0.99).The evaluation of individual responses revealed that participants with higher prescription of generics—reflected by a higher GBS—had higher incident risk of TI (mean GBS 3.61 for TI vs. 2.96 for n...

Nocebo in Biosimilars and Generics in Neurology: A Systematic Review

“…Finally in 2018, a web-based study among 90 neurologists (Saposnik et al, 2018), all of who prescribed MS treatments, demonstrated that half of them were primary or equal prescribers of generics or biosimilar MS drugs, a fact that was associated with a higher incident risk of “therapeutic inertia.” Factors associated with higher prescription of generics were older age, being a general neurologist, and more willingness to take risks in multiple domains.…”

“…In particular, from the physicians’ side, five studies found clearly investigating their perceptions about generic substitution (Guberman and Corman, 2000; Wilner, 2002; Berg et al, 2008a; Berg et al, 2008b; Saposnik et al, 2018). One study concerned neurologists; all prescribers of MS drugs (Saposnik et al, 2018) demonstrated that MS specialists were more concerned about generics/biosimilars. The remaining four studies were among clinicians who treated patients with epilepsy, and revealed significant unawareness of the process of generic substitution, knowledge gaps concerning special pharmacokinetic features of AEDs, and a general level of discomfort among neurologists to prescribe generic AEDs.…”

“…As for the study populations, varying sample sizes were identified. Several authors stated, as a limitation of their study, the limited number of patients included (Mikati et al, 1992; Guberman and Corman, 2000; Bautista et al, 2011; Abolfazli et al, 2012; Ngo et al, 2013; Fehse et al, 2015; Piguet et al, 2015; Ting et al, 2015; Faasse et al, 2016; Privitera et al, 2016; Vari et al, 2016; Bosak et al, 2017; Fanella et al, 2017; Markoula et al, 2017; Gha-Hyun and Dae, 2018; Saposnik et al, 2018), while two large population-based studies (Gollwitzer et al, 2016; Kesselheim et al, 2016) were included. Moreover, in five studies, patients’ recruitment was made from a tertiary epilepsy clinic (Guberman and Corman, 2000; Bautista et al, 2011; Bosak et al, 2017; Das et al, 2019; Gha-Hyun and Dae, 2018), thus making the generalization of their results difficult.…”

“…However, one study included a strict protocol for adherence and seizure documentation (Privitera et al, 2016), while another one excluded from analysis possible confounders that could contribute to breakthrough seizures (Berg et al, 2008a), and finally, another one study used a widely adopted measure of adherence in population-based studies (Gollwitzer et al, 2016). Measured clinical outcomes might need careful interpretation, as in some studies are based on self-reported data (Berg et al, 2008b; Das et al, 2018; Lang et al, 2018) or may be affected by external factors such as mass media advertisements (Rahman et al, 2017), or healthy policy and restrictive prescription rules (Saposnik et al, 2018), while some studies did not provide any data on AEs (Abolfazli et al, 2012; Reimers et al, 2017; Gha-Hyun and Dae, 2018). Many studies lacked pharmacokinetic data (Bosnyak et al, 2014; Vari et al, 2016; Bosak et al, 2017; Fanella et al, 2017; Gha-Hyun and Dae, 2018; Trimboli et al, 2018), while others provided (Ting et al, 2015; Privitera et al, 2016; Markoula et al, 2017; Reimers et al, 2017).…”

Comparison of Physician Therapeutic Inertia for Management of Patients With Multiple Sclerosis in Canada, Argentina, Chile, and Spain

“…However, all included countries shared private and government-funded MS drug coverage in the absence of private health insurance . A previous study showed a limited role of costs in explaining therapeutic decisions and TI. In addition, physicians’ performance on case scenarios might not accurately mirror real-life decisions, although such inconsistency would be expected to underestimate the true prevalence of TI among participants.…”