Marketing of a new non-sedating antihistamine (fexofenadine) puts an additional burden on healthcare system resources in Israel

Introduction

Current expert opinion on non-sedating antihistamines (NSAH) states that cetrizine, fexofenadine, and loratadine have similar clinical profiles in the treatment of diseases such as allergic rhinitis or urticaria [1–6]. Although single studies demonstrated some differences in efficacy and safety between currently available NSAH [7–16], it is commonly conceived by physicians that individual drugs of the NSAH therapeutic category have marginal advantages over one another [2–5].

Since the cost of prescribed drugs, including NSAH, continues to increase each year, decision makers are examining ways to control the escalating costs [17–22]. In the last few years, three new NSAH have been introduced onto the market in Israel (cetrizine, fexofenadine, and mizolastine).

The introduction of fexofenadine (as a new brand drug) onto the Israeli healthcare market was associated with an extensive marketing campaign. In the current study, we describe trends in the market share of NSAH in Israel. Our goal was to investigate the influence of a fexofenadine marketing campaign on NSAH market share within the Israeli healthcare system.

Methods

We performed a cross-sectional observational study on the market share of NSAH drugs, using data on drug sales retrieved from the administrative database of the Clalit Health Services (CHS), southern district. Data on drug sales of antihistamine were extracted for the time period between January 1998 and March 2001. Proportions of market share of each individual NSAH were described for the corresponding month of March during the study period. Different formulations or commercial products were grouped to form three groups of NSAH: fexofenadine, loratadine, and mizolastine.

Results

Throughout the study period, loratadine was the top-selling drug (Figure 1). Since its introduction, fexofenadine has had a steady increase in sales, alongside with a decrease in loratadine sales. Since December 2001 there has been a recovery in loratadine sales. The sales of cetrizine were steady over time.

Figure 1.  Proportion of users of fexofenadine, loratadine, and cetrizine (according to date).

In Table I, the relative costs and the proportion of users of each NSAH in March from 1998 to 2002 are described.

Table I.  Relative cost and proportions of users of NSAH in CHS, southern district, per month (March) between 1998 and 2002.

Year	1998	1999	2000	2001	2002	Relative cost
% astemiazole	19.6	16.8	0.3	0	0	+
% cetrizine	0	3.1	11.7	13.1	9.2	+ + +
% fexofenadine	0	0	0	10.2	33.4	+ + ++
% loratadine	64.1	67.7	81.4	71.9	56.4	+
% mizolastine	0	0	0	0.6	0.9	+ + +
% terfenadine	16.3	12.4	6.6	4.2	0.1	+
Total	100	100	100	100	100	–

χ² 5503, df = 16, p<0.001.

Discussion

In our study we describe shifts in the market share of NSAH sales within the healthcare system of the southern district CHS. Within 1 y, a substantial shift in market share occurred, with markedly increased sales of an expensive brand NSAH (fexofenadine), alongside a decrease in sales of a low-priced generic NSAH (loratadine) (Figure 1). The recovery of loratadine sales observed at the end of 2001 may be associated with the introduction of a generic formulation of the drug and its availability as an over-the-counter drug.

Similar observations, but with a lower magnitude, were described by the National Institute for Health Care Management Foundation in the United States [1]. Between the years 2000 and 2001, loratadine (as Claritin and Claritin Reditabs) dropped from 53% to 48% of the antihistamine market share, whereas fexofenadine (as Allegra) increased from 22% to 25%. In both the Israeli and the United States healthcare markets, the takeover of fexofenadine occurred after marketing campaigns.

In the United States, cetrizine (as Zytrec) captured 20–21% of the antihistamine market share in 2000–2001, as compared to 11.7–13.1% as observed in our study. We suspect the lower proportion of cetrizine use in Israel is due to the low profile of marketing by its manufacturing company.

The introduction of NSAH offers a major improvement in the treatment of allergic rhinitis, urticaria, pruritus (e.g. as in atopic dermatitis), and other allergic conditions [3] over first-generation antihistamines. They produce substantially less sedation and fewer anticholinergic effects, and most of the NSAH are taken once daily. No single agent of the NSAH group offers a superior clinical profile. However, it is beyond the scope of this paper to systematically review the topic. For further information, the reader is referred to a publication by Slater et al. [5] who described the difference between the drugs in the NSAH class.

The escalating costs of healthcare systems worldwide are in part due to the introduction of new technologies, including drugs [1]. As healthcare organizations have limited resources, priorities have to be set. Therefore, when a new and expensive technology is introduced, decision makers should determine whether it offers more than a marginal clinical benefit, using objective disease outcome measures. This is not the case when new drugs of the NSAH group were introduced into the healthcare market with marketing by drug companies [23]. Our results provide evidence that healthcare organizations should consider cost-benefit analyses before a new drug is introduced.

In summary, our study provides an observation on sale patterns of NSAH in Israel, which rapidly changed over time, consuming limited health resources. As different NSAH may provide only marginal clinical advantages over each other, we suggest that cost-benefit analyses should be performed by healthcare decision makers when considering the introduction of new drugs into a saturated market.