FirstWord Lists – The biggest biologics – still growing, growing, growing...

Over the past few weeks we have looked at the biggest selling drugs of 2013, the biggest growing drugs in 2013 and the biggest selling oncology drugs in 2013 (and 2018). Prominently encompassing each of these data sets are the industry's most commercially successful biologics.

The 10 biggest selling biologics in 2013 generated combined revenue of $68 billion and this list contains , if any, unfamiliar faces (particularly if you have spent time looking at the lists detailed above in recent weeks).

It remains pertinent, however, to revisit the commercial longevity of these franchises, particularly at a time when biosimilars remain an industry hot topic; thus, one key theme for these multi-billion dollar franchises is not where they are, but where are they going.

According to consensus estimates (sourced from Bloomberg), revenues for these 'elite' biologics will continue to cumulatively climb northwards over the next four years; by 2018 combined sales will have expanded to around $73 billion – an impressive statistic given that these drugs share an average age of 14 years (since launch).

Nevertheless, growth rates are slowing and four of the 10 products listed will see global revenues shrink over the next four years. The impact of significant biosimilar competition is barely visible, however; sales of Biogen Idec's Avonex will likely decline due to the recent entry of more convenient oral therapies in the multiple sclerosis market, while forecast sales declines for Herceptin and Rituxan are heavily shaped by the launch of successor biologics by Roche (Perjeta/Kadcyla and Gazyva, respectively) - 2013 In Review – Roche's biosimilar defence strategy gains momentum.

Partially demonstrating the limited impact that biosimilars are expected to have on their branded equivalents (according to analyst forecasts at least) is the relatively flat performance of Johnson & Johnson's Remicade. With European approval of biosimilar infliximab products occurring last year – and expiration of relevant intellectual property facilitating its launch in major EU markets from early 2015 – Remicade is the only leading branded antibody with visible biosimilar competition in a western market (see Spotlight On: Norway unveils near 40 percent discounting for biosimilar infliximab – can it pave the way for a broader European trend?

Only the forecast performance of Amgen's Neulasta has a 'hint' of biosimilar competition; an absolute decline in sales of around $1 billion over the period 2013-18 most likely bakes in some erosion via short-acting filgrastim products.

As biologics keep 'winning,' it is AbbVie, Roche and Sanofi that look set to benefit the most over the next few years. AbbVie's Humira is expected to expand its leadership of the anti-TNF space – and deliver an absolute increase in sales of around $5 billion in the process – while revenues generated by Sanofi's long-acting basal insulin are expected to expand significantly; a trend boosted by recently disclosed legal moves to delay a competitor product being launched by Eli Lilly – see ViewPoints: Delay to biosimilar Lantus – let the pricing party continue.

Roche's ability to extend and enhance its existing cancer antibody franchises via the launch of new products that have been deemed to advance the standard of care is arguably the most impressive achievement among the leading biologic players – who said lightening doesn't strike twice?

See also ViewPoints: Money for nothing? – Indication extrapolation remains key issue for biosimilar developers and ViewPoints: Fool's gold - will only the few strike rich in biosimilars?

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