Pfizer was celebrating on both sides of the Atlantic yesterday, after its cancer drug Sutent won approval in the USA and inhaled insulin Exubera got the go-ahead in Europe.

Sutent and Exubera are two of Pfizer’s most important new products as the company weathers patent expiries on existing brands that could carve up to $14 billion off its revenues.

The US Food and Drug Administration has cleared Sutent (sunitinib) to treat patients with gastrointestinal stromal tumors (GIST), a rare stomach cancer, as well as advanced kidney cancer – the first time a cancer drug has been cleared for two indications right off the bat.

Sutent will be used initially in GIST patients who have not responded to treatment with Novartis’ Gleevec (imatinib), currently the only approved treatment for this type of cancer, based on clinical data showing that Pfizer’s drug delays the time for tumours to progress to 27 weeks compared to just six weeks for untreated patients.

Gleevec, sold as Glivec in some markets, has been a major commercial success for Novartis, racking up sales of $2.2 billion in 2005, a rise of more than 30%. It is approved for GIST as well as chronic myeloid leukaemia. Despite its second-line labelling, Sutent is expected to have an immediate impact on treatment because many patients develop resistance to Gleevec within 18 months of treatment.

Meanwhile, Sutent’s approval for patients with advanced renal cell carcinoma was based on data showing it can reduce the size of tumours in patients, with an overall response rate of 26%-37%. In this indication, Sutent will go head-to-head with another new product, Bayer and Onyx’ Nexavar (sorafenib tosylate), which was cleared by the FDA last month.

Both of these orally-active drugs have been tipped as potential blockbusters in kidney cancer, because current treatment with interleukin-2 or interferon-alfa tends to have serious side effects and has to be delivered by injection. For Pfizer the drug also marks its first major foray into the cancer sector.

First inhaled insulin for diabetes

Meanwhile, the news that the European Medicines Agency has approved Exubera marks the end of a long and winding road for Pfizer and its development partner Nektar Therapeutics.

Despite delays on the way to market caused by a worry about the product’s long-term effects on lung function, Exubera can now be launched with a clear lead over its nearest rivals in pulmonary insulin delivery, Eli Lilly/Alkermes and Novo Nordisk/Aradigm, and puts it on track to secure the billion-dollar plus sales expected for this type of product.

Exubera is the first non-injectable insulin product to be approved for marketing in a major pharmaceutical market (although Canadian biotech concern Generex recently introduced an oral spray version in Ecuador). It is intended as a replacement for short-acting insulin, and is inhaled just before meals.

Pfizer now owns commercial rights to the product, after buying out former partner Sanofi-Aventis in a $1.3 billion deal earlier this month. US approval could be forthcoming as early as today.