When Abbott announced its full-year results  last week, its anti-TNF inhibitor product Humira delivered a stronger-than-expected 23.1 percent year-on-year increase in Q4 sales (recorded at $2.7 billion). Annual sales for 2012 stood at $9.3 billion, cementing the status of Humira as one of the biggest selling products of all time.
Measured in terms of peak annual sales, Humira revenues in 2012 were marginally below the combined sales of Plavix recorded by Bristol-Myers Squibb and Sanofi in 2011. However, while Plavix revenues are now undergoing a dramatic decline following US patent expiry last year, Humira continues to act as a key growth product for Abbott/AbbVie, and is expected to do so for some time.
Based on an annualised Q4 2012 performance, Humira sales would stand at $10.7 billion; thus full-year revenues for 2013 can be expected to easily outstrip those of Plavix and move closer to the peak $13.7 billion figure set by Pfizer's Lipitor.
Whether peak annual Humira sales will ever reach the Lipitor benchmark is open to conjecture. Current consensus forecasts indicate that sales of the anti-TNF product will peak at $11.2 billion in 2016, before a steady decline driven in part by loss of market share to oral alternatives, such as Pfizer’s Xeljanz. That said, if Humira can maintain the growth momentum seen in Q4 2012, these estimates may be revised upwards.
Illustrated in the table above, FirstWord has identified 19 products which have delivered peak annual global sales in excess of $5 billion.
Tellingly, each of the products in the list best positioned to record an increase in peak annual sales over the next five years is a biologic; Humira, Enbrel, Rituxan, Herceptin and Lantus being the chief candidates. This is driven by a number of factors – the later launch of certain brands, for example – but also illustrates the robustness of leading biologic franchises that do not face direct substitutable generic competition.
Thus, a number of the biggest selling biologic therapies are forecast to deliver substantial cumulative revenues once they have passed peak year sales. Roche’s Rituxan is a case in point – consensus forecasts indicate peak sales of $7.3 billion in 2015, although annual revenue is then expected to remain pegged at around the $7 billion mark for a number of years.
A lack of small molecules expected to deliver significant growth moving forward demonstrates both the effects of the patent cliff and reduced ability by the industry to bring more products of this type/revenue scale to the market.
Cumulative revenue analysis
Closer analysis of cumulative sales across the five biggest selling products on a peak annual sales basis provides for some interesting trends.
Four of the five products (Humira being the exception) were launched within a two year period (1997-1999) – a statistic which tells its own story. The figure below details cumulative revenues derived from each franchise since 2000, and while direct product-by-product comparisons are difficult it is useful for illustrative purposes.
The first observation is that from a commercial perspective Lipitor is a truly unique product, having generated cumulative global revenues of approximately $130 billion since 2000. Former head of Pfizer R&D John LaMattina has described its sales performance as an "aberration" that will not be repeated (the ramp in sales between 1997 and 2000 – when revenues reached $5 billion – is best described as staggering).
Of the other products it is the small molecule, primary care drugs Plavix and Seretide that have accumulated the highest revenues over the past 11 years, at $73 billion and $62 billion, respectively. However, the susceptibility of this product type to generic erosion is illustrated by forecast cumulative revenues for Plavix over the next five years, at $16.1 billion. Seretide – which is likely to avoid direct substitutable competition for most of this period despite loss of patent exclusivity – is forecast to deliver cumulative sales of $32.2 billion.
Reflecting in part its later launch – but also its market characteristics – Humira is forecast to contribute revenues of around $58 billion between 2013 and 2017, while Enbrel is forecast to contribute $45 billion. Thus Humira will further cement its status as one of the industry’s biggest selling products of all time over the next few years, and given uncertainty both in terms of branded and biosimilar competition, perhaps will catch the peak annual sales level set by Lipitor.
The list of pharmaceutical products detailed above reflects the ‘golden age’ of the blockbuster; the industry is no longer able to deliver products that hold this level of commercial potential to the market with nearly as much regularity. Indeed, looking at current late-stage pipelines, there is only one product that analysts are confident will deliver peak annual sales in excess of $5 billion in the medium term; Gilead Sciences’ oral hepatitis C treatment sofosbuvir.