Updated

Merck & Co. said results from a Phase III clinical study showed its investigational allergy immunotherapy tablet reduced ragweed allergy symptoms in adults.

Merck has partnered with the Danish pharmaceutical company ALK-Abello A/S (ALK-B.KO) to develop allergy immunotherapy tablets, or AITs, to treat allergies caused by ragweed pollen, grass pollen and house dust mites in North America.

The companies plan to file new drug applications for ragweed and grass AITs with the U.S. Food and Drug Administration in 2013.

"Merck is pleased that patients who took its AIT in this study experienced a significant reduction in the nasal and eye symptoms caused by ragweed allergies, and these positive results are an important step in the development of this investigational therapy," said Rupert Vessey, senior vice president and franchise head of Respiratory and Immunology at Merck Research Laboratories.

The Phase III trial was designed to assess the effectiveness and safety of two doses of ragweed AIT during peak ragweed season. Patients treated with a once-daily tablet at a dose of 12 Amb a 1-U showed a 27 percent reduction in symptoms while those treated with a 6 Amb a 1-U dose showed a 21 percent reduction.

The most frequently reported side effects were itchy mouth and ear and throat irritation.

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