Genmab A/S announced that the US Food and Drug Administration (FDA) has placed a partial clinical hold on zalutumumab clinical studies being conducted under the US Investigational New Drug (IND) application, as well as requests for new studies. The affected studies are the phase-II study in patients with head and neck cancer considered incurable with standard treatment and the phase-I/II front line study of zalutumumab in combination with chemo-radiation.

The partial clinical hold does not affect the two ongoing phase-III studies of zalutumumab in head and neck cancer or the phase-I/II study of zalutumumab in combination with radiotherapy as these are conducted outside the US IND. Results from the pivotal phase-III study in refractory head and neck cancer, for which 264 patients have been recruited to date, are still expected by the end of 2009.

A partial clinical hold is a delay or suspension of only part of the clinical work requested under an IND. Under the partial clinical hold on zalutumumab, patients already enrolled in the phase-II and phase-I/II studies who are not experiencing serious adverse events may continue to receive treatment, however, no additional patients may be enrolled.

The FDA has requested an updated analysis of safety data since the company's most recent annual report which covered the period through July 29, 2008. Genmab is working to respond to the request and expects to make the required submission shortly.

"Genmab is fully committed to working with the FDA to meet their requests for additional information and to resume enrollment in the affected zalutumumab clinical trials as quickly as possible," said Lisa N Drakeman, chief executive officer of Genmab.

Zalutumumab is a high-affinity human antibody that targets the Epidermal Growth Factor receptor (EGFr), a molecule found in abundance on the surface of many cancer cells, and is a well validated target.