Publications

UNLABELLED

High titer antibodies to type 1 interferons have been recently reported as being highly specific for patients with autoimmune polyglandular syndrome type 1 (APS1) in Finnish and Norwegian patients with mutations in the AIRE gene. Those studies employed a complex neutralization assay to define the type 1 interferon autoantibodies. Here we have established a competitive europium time resolved fluorescence assay for IFN-alpha autoantibodies and measured sera from subjects with APS1, first degree relatives of APS1 patients, patients with Addison's disease or Type 1 diabetes. The europium-based immunoassay utilizes plate bound human IFN-alpha incubated with sera with or without competition with fluid phase IFN-alpha, followed by anti-IgG biotinylated antibody and detection with streptavidin-europium. The index of IFN-alpha Ab was calculated as (CPS (Counts per second) without competition-CPS with competition)/(CPS positive standard sera without competition-CPS positive standard sera with competition). RESULTS are reported for raw CPS and indices and are compared across the different subjects.

RESULTS

For normal controls (n=100) CPS without competition were 31,237+/-17,328 CPS while after subtracting the competition value, the results were -6563+/-10,303 CPS. The initial APS1 patient (used to create the index as 1.0) gave 394,063 CPS without competition and a delta of 363,662+/-31,587 CPS with competition. Scatchard plot analysis of this patient sample revealed a high avidity for IFN-alpha (K(d) of 0.5 nM). The CPS, delta, and index for 6/7 APS1 patients were strongly positive and 3 standard deviations or more above that of the normal controls. Using a cut-off of 2 standard deviations above normal controls, relatives of APS1 patients were negative for type I interferon autoantibodies as were 71 patients with Addison's disease (non-APS1) and 141 Type 1 diabetes patients. This simple high throughput competitive europium time resolved fluorescence assay had a sensitivity of > or =86% or greater and a specificity of >99.5%.

PURPOSE

CP-724,714 is an orally available, small molecule, potent HER-2 tyrosine kinase inhibitor under development for the treatment of advanced HER2-overexpressing cancers. In this study, the influence of baseline clinical characteristics and pathophysiological variables on the pharmacokinetics (PK) of CP-724,714, and the correlation between PK exposure and safety were examined in patients treated in the First-in-Human trial. PK and safety were also simulated for a Phase 2 trial at the recommended Phase 2 dose (RP2D) to assess if the simulated PK exposures of CP-724,714 covered the preclinically predicted efficacious concentrations, and if the predicted incidence of hepatic toxicities (>or=CTC grade 3) was acceptable.

METHODS

Patients (n = 30) with advanced malignant HER2 positive solid tumors were enrolled in this open label dose-escalation study, and treated with daily oral dosing of CP-724,714 in 21-day cycles at the following dose levels: 250 mg QD, 250 mg BID, 400 mg BID, and 250 mg TID. PK parameter values were estimated using noncompartmental techniques. PK exposure parameters were correlated with the baseline pathophysiological variables, clinical characteristics, and safety. The simulations of PK exposures and the incidence of >or=grade 3 liver toxicity at the recommended Phase 2 dose were performed by nonparametric bootstrap (n = 1,000).

RESULTS

C (max) and AUC increased in an approximate dose proportional manner. The terminal t (1/2) was approximately 4.5 h, and was constant across the dose range from 250 to 400 mg. There was some accumulation with BID and TID dosing with a mean AUC accumulation ratio approximately 1.2-1.5, consistent with the t (1/2). Inter-patient variability in PK parameters was 31-65%, resulting in a considerable overlap of systemic exposure parameters (C (max) and AUC) at higher doses (i.e., 250 mg TID and 400 mg BID), as expected for the narrow dose range. Significant correlations were observed for body size and oral clearance (CL/F) (r = 0.574, P = 0.001) and oral steady-state volume of distribution (V (dss)/F) (r = 0.669, P = 0.0001). The most frequently encountered toxicities were elevated ALT and AST, hyperbilirubinemia, rash, asthenia, and nausea/vomiting (N/V). The steady-state AUC0-24 h was significantly correlated with the elevation of total bilirubin (r = 0.670, P = 0.001), ALT (r = 0.548, P = 0.002), and AST (r = 0.461, P = 0.010). The simulation of the Phase 2 trial at 250 mg BID predicted that the 95% confidence interval of the simulated mean concentrations of CP-724,714 were above the preclinically predicted efficacious concentrations throughout the majority of the dosing interval. The probability for >or=33% incidence of grade 3 or greater elevations of liver function test (LFT) was low (1.1%).

CONCLUSIONS

CP-724,714 demonstrates linear single-dose and multiple-dose PK. Both CL/F and V (dss)/F correlate with body size. Elevations of ALT, AST, and total bilirubin positively correlate with the steady-state AUC0-24 h. The Phase 2 trial simulation suggests that CP-724,714 will be well tolerated and that PK exposures will exceed the preclinically predicted efficacious level at the recommended Phase 2 dose (250 mg BID), supporting further evaluation of CP-724,714 in the Phase 2 trial.

Up to 80% of patients with scleroderma have lung disease, with interstitial lung disease (ILD) being the most common manifestation. Currently, there is no definitive therapy for this condition. The objective of the study is to investigate the use of mycophenolate mofetil (MMF) to treat scleroderma interstitial ILD. We report a retrospective chart review of 17 patients with scleroderma ILD treated with MMF (2g/day) for at least 12 months. Demographics, bronchoalveolar lavage (BAL) findings, pulmonary physiology and high-resolution computed tomography were recorded at baseline and after 12 and 24 months of therapy. Baseline BAL (n=12) showed alveolitis (median of 18% neutrophils). Ninety-four percent of subjects had either improved or stable lung function after 12 months of treatment: four improved, 12 were stable and only one worsened. All patients had radiographic abnormalities consistent with ILD. After 12 months of therapy, radiological findings (n=15) were stable in 11 patients, worse in three, and improved in one. There were no side effects attributable to MMF therapy recorded. Treatment of patients with scleroderma ILD for up to 24 months with MMF was generally associated with stable pulmonary function. These data argue for a prospective trial using MMF to treat scleroderma ILD.