Molecule of the Month

Abstract

The most prescribed and top selling drugs of 2006: generics, biologics and, of course, Lipitor™. In the spring of 2007, data for the top 200 prescription drugs, in terms of both sales and number of dispensed prescriptions, was released [1-3]. Total sales of prescription drugs reached $275 billion in 2006, an impressive 8.3% increase from 2005; in contrast, sales only increased 5.3% over 2004. The number of dispensed prescriptions also increased in 2006 to 3.7 million (a 4.6% increase from 2005) [1-3]. These data are very encouraging for the pharmaceutical industry, especially considering that 2006 witnessed the loss of patent protection for blockbusters Zocor™, Zoloft™, Plavix™, Provochol™ and Mobic™ which fell victim to generic competition. In fact, the overriding theme of the 2006 was a significant increase in generic prescriptions and sales. While many factors play a role, the 8.3% increase in sales is primarily due to the successful launch of the full Medicare Part D benefit which extended prescription drug coverage benefits to US citizens that historically had little to no coverage. Medicare Part D encompasses every major class of pharmaceuticals and, in 2006, 63% of all prescriptions dispensed to Medicare Part D beneficiaries were generic products [1-3]. Alarmingly for big Pharma, the number of generic products is growing (the FDA approved 371 new generic products in 2006 and their number is expected to further increase in 2007), and drug plans can be expected to elect lower cost generics in preference to name brand drugs. What is the effect of generic competition for a well established, safe and effective drug? Mercks Zocor™ is a good example. In 2005, the statins Lipitor™ and Zocor™ were ranked No.1 ($7.6 billion) and No.2 ($ 4.5 billion) in sales, and No. 1 and No. 11 in prescriptions dispensed, respectively. After generic variants of Zocor™ entered the market mid-year 2006, Pfizers Lipitor™ remained No. 1 in terms of both sales ($ 8.6 billion) and prescriptions dispensed (74,020) while Zocor™ slid to No.7 in sales ($3.2 billion) and No. 25 in prescriptions dispensed. It will be interesting to see impact of generic Zocor™ on Lipitor™ sales in 2007, as drug plans steer towards the cost savings of generic statins. Also in 2007, the industry will witness first time generic competition for a number of other ‘blockbuster’ drugs such as Prevacid™ (No. 5 in 2006 sales at $3.6 billion) [1-3]. In 2006, the top 10 products in the US market by sales were: 1) Lipitor™ ($ 8.6 billion), 2) Nexium™ ($ 5.1 billion), 3) Advair Diskus™ ($ 3.95 billion), 4) Aranesp™ ($ 3.94 billion), 5) Prevacid™ ($ 3.5 billion), 6) Epogen™ ($ 3.2 billion), 7) Zocor™ ($ 3.1 billion), 8) Enbrel™ ($ 3.08 billion), 9) Seroquel™ ($ 3.02 billion), and 10) Singulair™ ($ 3.0 billion) [1]. These 10 products accounted for 15% of total sales of the top 200 drugs in 2007, and three of the top 10 (Aranesp™, Epogen™, Enbrel™) are biologics. Indeed, 2006 witnessed an increase not only in generic drug sales and prescriptions dispensed, but also biologics. Amgens Aranesp™ significantly led all top 20 earners with a 42% increase in revenue over 2005 [1-3]. IMS Health forecasts continued sales growth in the pharmaceutical sector in the 6% to 9% range through 2010 and predict that both generic and biologic sales will grow more rapidly and lead the market [1-3]. How will these emerging trends impact big Pharma, the biotech industry, branded drugs and non-biologic small molecule drug sales? Only time will tell, but there are clear challenges to an already struggling pharmaceutical industry. REFERENCES [1] Lamb, E. Top 200 prescription drugs of 2006. Pharmacy Times, May 2007, pp.1-4, and reference therein. [2] IMS Health. Press release. March 8, 2007, www.imshealth.com [3] For more information on generic drug approvals and impact on sales see the US Food and Drug Adminstration: www.fda.gov.