BOULDER, Col. ( TheStreet) -- Clovis Oncology ( CLVS) and AstraZeneca ( AZN) are locked in a tight and very competitive race to develop two similar, targeted lung cancer drugs. Healthcare investors are watching closely, naturally. On Wednesday, a somewhat disappointing clinical update from Clovis swung momentum every so slightly in AstraZeneca's direction.
But that was enough to send Clovis shares dropping 7.5% to $49.7, extending the Boulder, Co.-based biotech company's 2014 decline to 17.3%. Meanwhile, AstraZeneca were rising 0.8% to $74.56.
The Clovis lung cancer drug is known as rociletinib. On Tuesday night, Clovis released an update on a phase II study in which lung cancer patients expressing the T790 mutation demonstrated an overall response rate of 67% and a median progression-free survival of 10.4 months following treatment with two different doses of rociletinib.
The new rociletinib lung cancer data are only disappointing in the context of Wall Street and the competitive situation with AstraZeneca. Investors were hoping/expecting to see the updated median progression-free survival stay around 12 months, where it was in June when Clovis last disclosed results from the rociletinib study. This compares to a median progression-free survival of 9.6 months for AstraZeneca 's lung cancer drug AZD9291 disclosed in a September update. Making cross-study comparisons are fraught with peril but that's never stopped investors from doing it.
"A lot of people (including the Street analysts) are carefully scrutinizing and dissecting the data for winners and losers, but the real truth is that most oncologists would be delighted to have a choice for a difficult to treat patient population," said cancer drug consultant and well-known blogger Sally Church.
The progression-free survival data for rociletinib presented Tuesday night are also relatively immature, which means the 10.4 month-figure could move one way or the other as patients are followed for longer period of time.
Both Clovis' rociletinib and AstraZeneca's '9291 are designed to be effective against non-small cell lung cancer containing a genetic mutation known as T790M, which renders tumors resistant to treatment with drugs like Roche's (RHHBY) Tarceva. Both companies are conducting phase III studies of their respective drugs right now, so the race is on to compile data and submit to U.S. and European regulators as quickly as possible. On Tuesday, AstraZeneca announced plans to submit an approval filing for '9291 in the second quarter of 2015. Clovis' current guidance is for an rociletinib approval filing "mid-year" 2015.
Hypergylcemia, or high blood sugar, is the most concerning side effect related to rociletinib. In the update, however, the rate of serious hyperglycemia fell to 14% versus 22% in the June update. Lung cancer patients experiencing serious increases in high blood sugar while on rociletinib are treated with metformin, a common anti-diabetes medicine.