Production and clinical development of a Hansenula polymorpha-derived PEGylated hirudin.

This article describes the expression of the hirudin gene heterologously in the methylotrophic yeast Hansenula polymorpha, the establishment of an industrial-scale production process and the subsequent clinical development of polyethylene glycol (PEG)-hirudin. PEGylation increases the molecular weight of hirudin, thereby reducing its kidney filtration rate and immunogenicity and increasing its half-life in the circulation.

Safety, activity, and pharmacokinetics of GLQ223 in patients with AIDS and AIDS-related complex.

GLQ223 is a highly purified single-chain ribosome-inactivating protein with selective effects against a variety of cells, including macrophages infected with human immunodeficiency virus. We evaluated the safety, pharmacokinetics, and immunologic effects of multiple doses of GLQ223 in 22 patients with AIDS or AIDS-related complex; CD4+ T-cell counts were between 100 and 350/mm3. GLQ223 was administered intravenously at doses of 8, 16, 24, 36, and 50 micrograms/kg of body weight; the drug was administered by constant infusion over 3 h to achieve a concentration in serum of 50 ng/ml; this concentration is known to be associated with anti-HIV effects in vitro. All patients reported a flu-like syndrome characterized by muscle and joint aches and an increase in creatinine kinase levels; symptoms were controlled easily. For patients who received 36 and 50 micrograms/kg, target concentrations in serum were achieved and an increase in CD4+ and CD8+ T cells was sustained; this sustained increase persisted for at least 28 days after the last infusion. beta 2-Microglobulin levels increased during the infusions and then declined when the infusions ended. Repeat infusions of GLQ223 were safe and relatively well tolerated. The target concentration of GLQ223 in serum was achieved and sustained. Our results suggest that GLQ223 may have activity in treating patients with human immunodeficiency virus infection.

Observations using antiendotoxin antibody (E5) as adjuvant therapy in humans with suspected, serious, gram-negative sepsis.

OBJECTIVE: To evaluate the safety and efficacy of E5 (Xomen-E5), a murine monoclonal immunoglobulin M antibody, in reducing mortality in patients with serious Gram-negative infections. Phase II, single-site study. DESIGN: Randomized, double-blind, placebo-controlled study. SETTING: Surgical, neurosurgical and medical ICUs, comprising approximately 30 beds in a multidisciplinary university hospital. PATIENTS: Patients with clinical evidence of serious infection admitted to the ICU for monitoring of vital signs and for intensive care nursing. Of the 39 patients enrolled in the study, 23 had documented Gram-negative infection. METHODS: Patients suspected of having life-threatening Gram-negative infections received one of two doses of E5 or placebo. Safety and efficacy were assessed by survival on days 3, 7, and 21, appearance of adverse reactions, development of antimurine antibodies, and effects on BP, urine output, WBC count, and temperature. MEASUREMENTS AND MAIN RESULTS: Mortality rate from Gram-negative infection 3 days after the last drug (or placebo) infusion was two (22%) of nine deaths in the placebo group compared with 0 of nine for E5 2.5 mg/kg and 0 of five for E5 7.5 mg/kg. At 21 days after therapy, three patients treated with E5 had died. Only one of these three deaths resulted from infection. Eight of 15 E5 patients tested had immunoglobulin G antimurine antibodies by 3 wks after therapy began, but all were asymptomatic. CONCLUSIONS: E5 was well tolerated and may have the potential to reduce early morbidity and the mortality rate in seriously ill patients with Gram-negative infections. Results from larger phase III studies are needed to confirm these findings.

The role of monoclonal antibodies in the management of gram-negative sepsis. Experience with the E5 antibody.

Immunologic targeting of the mediators of sepsis is a new approach to reducing mortality associated with this often-fatal complication. When sepsis is due to infection with a gram-negative pathogen, endotoxin plays a key role in its pathogenesis. Antiendotoxin antibody E5 binds endotoxin from a broad spectrum of clinically relevant gram-negative bacteria and reduces mortality from endotoxemia and bacteremia in animal models. It seems to be safe to administer to patients with suspected gram-negative sepsis; fewer than 2% of patients experienced allergic-type reactions, a frequency similar to that seen with third-generation cephalosporins. When administered in a dose of 2 mg/kg daily for two days, E5 reduces mortality and improves the outcome of multi-organ failure in patients with gram-negative sepsis, especially when administered before the development of refractory shock. Patients with sepsis of other etiology have not been shown to benefit from antiendotoxin immunotherapy. E5 antibody appears to be an effective agent for the adjunctive treatment of gram-negative sepsis. Further evaluation of E5 antibody is warranted in the treatment of patients with neutropenia, burns, and shock.

Randomized, double-blind phase II study of anti-endotoxin antibody (E5) as adjuvant therapy in humans with serious gram-negative infections.

Xomen-E5 (E5) is a murine monoclonal IgM antibody (MAb) that binds to the lipid A epitope of endotoxin. The MAb was developed by immunization against the J5 mutant of Escherichia coli. Prior studies in humans have shown safety and T1/2 of 18.4 hours. In this double blind study patients suspected to have life threatening gram-negative infections were randomized to receive 2 doses, 24 hours apart, of placebo (P), 2.5 mg/kg E5, or 7.5 mg/kg E5. Overall 23 patients had a documented serious gram-negative infection and received at least one dose of study drug. Mortality 3 days after last infusion was 2 of 9 for P, 0 of 9 for 2.5 mg/kg, and 0 of 5 for 7.5 mg/kg. By 21 days after therapy one E5 treated patient had died. Wheezes occurred in one E5 treated patient. Eight of 15 E5 patients treated had IgG anti-murine antibodies by 3 weeks after therapy. These data suggest the need to pursue studies designed to verify that E5 reduced mortality and morbidity in seriously ill patients with gram-negative infections.