LeuTech.

Abstract

LeuTech is a sterile, lyophilised kit-packaged diagnostic system containing murine anti-CD15 IgM monoclonal antibody proprietary radiolabelled with technetium 99m ((99m) Tc) for infection imaging. After intravenous injection of LeuTech, diagnostic imaging can be obtained within 1h with conventional planar gamma camera techniques. LeuTech binds to neutrophils in vivo at the infection site. LeuTech is a fast (1h to obtain image), convenient (one-step injection), safe, effective (bright, clear images) and cost-effective diagnostic for existing and new nuclear imaging markets including chronic and acute indications such as appendicitis, ischaemic bowel, post-surgical infection and nosocomial infection. Palatin Technologies has successfully completed a Phase III trial with LeuTech in 203 patients at 10 sites in the USA for the detection of equivocal appendicitis. A BLA with the US FDA for LeuTech has been filed for the diagnosis of equivocal appendicitis. The US FDA has recommended LeuTech for approval for the diagnosis of appendicitis in patients with equivocal signs and symptoms. On 28 September 2000 Palatin received a 'complete review' letter from the FDA regarding the BLA for LeuTech. While, there were no further data requested on the safety and clinical efficacy of LeuTech, FDA requested some manufacturing, quality control and validation steps and data to be completed prior the approval of LeuTech. Palatin plans to finalise the amendments to BLA in the H2 of 2002. LeuTech is also being investigated in Phase II clinical trials for the diagnosis of osteomyelitis in 45 patients at four sites. Positive interim results from a Phase II clinical study conducted in 19 patients with diabetic foot ulcers and suspected osteomyelitis were announced at the Society of Nuclear Medicine Annual Meeting, Toronto, Canada, in June 2001. Imaging with LeuTech provided a diagnostic image within 1 hour compared with the 24 hours required to obtain an image using standard-of-care diagnostic, Indium oxide-labelled white blood cells. Walter Reed Army Medical Center is evaluating LeuTech for early detection of inhalation anthrax. LeuTech is planned to be evaluated for the detection of osteomyelitis secondary to joint replacements (such as hip replacement), postoperative abscesses, ulcerative colitis and other intra-abdominal infections (colitis, spleen or urinary tract). Palatin Technologies has exclusive rights to murine anti-CD15 IgM monoclonal antibody from The Wistar Institute of Biology and Anatomy. LeuTech has been licensed to Mallinckrodt worldwide, except for Europe. In October 2000, Mallinckrodt was acquired by Tyco International. On 15 May 2002, Palatin Technologies announced that its agreement with Tyco/Healthcare/Mallinckrodt regarding LeuTech marketing was amended to require Mallinckrodt to pay an additional $3.2 million to cover half of Palatin's expenses for the completion of the FDA's review. The additional funding is conditional upon reaching of certain milestones with Palatin receiving $800,000 within ten days of the signing of the amendment. Under the terms of the original agreement (1999), Palatin received a licensing fee of $500,000 and $13 million for the stock. All expenses prior to FDA approval were equally shared. Palatin will manufacture LeuTech and will receive a transfer price per unit and also royalties on net sales.