Allergan's stock has taken a hit - despite posting better-than-expected first-quarter results - after the group revealed it will delay Phase III testing of its investigational eye drug on weak mid-stage data.

The Irvine, California-based company had reportedly been on track to kick off late-stage trials of DARP-in in patients with macular degeneration by the end of the year, but now says early-stage data do not support a direct move to Phase III at this time, pushing shares down 13%.

But Allergan's troubles pushed shares of Regeneron up 11% in afternoon trading yesterday, as its investors welcomed the possibility that delays could help increase sales of the latter's rival eye drug Eylea.

News of the delay came as the company booked strong organic growth in net income for the first quarter.

Reported net income plummeted to $12.5 million from $229.8 million the prior year, largely because of a $259-million one-time charge relating to discontinued operations, reportedly from the planned sale of its Lap Band obesity implant business.

But taking extraordinary items out of the equation the firm did pretty well, generating an 18% rise in earnings per share from continued operations to $0.98.

Product sales jumped 8.4% to $1.43 billion, driven by a 15% rise in Botox sales to $458 million and a 10.2% leap in turnover of medical devices to $201 million (excluding Lap Band).

But Allergan did adjust its full-year earnings expectations, lowering it to $4.70- $4.76 per share from $4.75 to $4.83 per share, because of the dilutive effect of its acquisition of MAP Pharmaceuticals.