BASEL, Switzerland—Novartis reported solid results for the second quarter ending June 30, 2015, despite a weak performance by Alcon, its eyecare business unit.

Novartis generated net sales of $12.7 billion in second quarter, a 6 percent increase in constant currencies over year-ago. Operating income was $2.3 billion, a 14 percent drop in constant currencies, but core operating income rose 5 percent in constant currencies, to $3.6 billion.

Alcon net sales of $2.6 billion were flat for 2Q versus year-ago, mainly driven by lower surgical equipment sales, a decline in intraocular lens (IOL) sales due to competitive pressure, and an accelerated contact lens care decline. In addition, Alcon was negatively impacted by approximately 2 percent from the phasing of U.S. allergy shipments, as well as trade inventory reductions, resulting in flat growth (cc) in the second quarter, according to Novartis.

Alcon’s operating income plummeted to $150 million, a 41 percent drop in constant currencies, reflecting a $119 million intangible asset impairment. Core operating income fell 10 percent in constant currencies to $796 million, primarily impacted by product mix and slightly higher revenue provisions, as well as higher spending in R&D and M&S, Novartis said. Core operating income margin in constant currencies decreased by 3.7 percentage points; currencies had a negative impact of 1.8 percentage points, resulting in a net decrease of 5.5 percentage points to 31.1 percent of net sales.

In the first half of 2015, Alcon posted net sales of $5.1 billion, up 2 percent in constant currencies. Surgical sales increased 2 percent in constant currencies, as solid cataract and vitreoretinal consumables sales were partly offset by lower equipment sales and competitive pressure on IOLs. Ophthalmic pharmaceuticals grew 3 percent in constant currencies, benefitting from double-digit growth of Systane in dry eye and fixed-dose combination products in glaucoma. Vision care, which was up 1 percent in constant currencies, was driven by strong continued uptake of Dailies Total1 and AirOptix Colors, but was offset by a continued decline in contact lens care and reduction in U.S. trade inventories of contact lenses, according to Novartis.

Operating income amounted to $503 million, a 12 percent drop in constant currencies, reflecting the second quarter intangible asset impairment of $119 million. Core operating income was $1.7 billion, down 1 percent in constant currencies, primarily impacted by product mix and slightly higher revenue provisions, as well as higher spending in M&S. Core operating income margin in constant currencies decreased by 1.1 percentage points; currencies had a negative impact of 1.7 percentage points, resulting in a net decrease of 2.8 percentage points to 33.0 percent of net sales.