Phase 1 study of single-agent WNT974, a first-in-class Porcupine inhibitor, in patients with advanced solid tumours.

BACKGROUND: This Phase 1 study assessed the safety and efficacy of the Porcupine inhibitor, WNT974, in patients with advanced solid tumours. METHODS: Patients (n = 94) received oral WNT974 at doses of 5-30 mg once-daily, plus additional dosing schedules. RESULTS: The maximum tolerated dose was not established; the recommended dose for expansion was 10 mg once-daily. Dysgeusia was the most common adverse event (50% of patients), likely resulting from on-target Wnt pathway inhibition. No responses were seen by Response Evaluation Criteria in Solid Tumors (RECIST) v1.1; 16% of patients had stable disease (median duration 19.9 weeks). AXIN2 expression by RT-PCR was reduced in 94% of paired skin biopsies (n = 52) and 74% of paired tumour biopsies (n = 35), confirming inhibition of the Wnt pathway. In an exploratory analysis, an inverse association was observed between AXIN2 change and immune signature change in paired tumour samples (n = 8). CONCLUSIONS: Single-agent WNT974 treatment was generally well tolerated. Biomarker analyses suggest that WNT974 may influence immune cell recruitment to tumours, and may enhance checkpoint inhibitor activity. CLINICAL TRIAL REGISTRATION: NCT01351103.

No conclusive evidence that histologically found granulomas and acute local reactions following hylan G-F 20 injections are related or have clinical significance.

Osteoarthritic (OA) knee pain can be successfully treated with hylan G-F 20 (Synvisc, Sanofi Biosurgery, Cambridge, MA) with few local adverse events. However, a few studies have identified hyaluronate positive (HA+) granulomas in the synovial tissue of patients treated with hylan G-F 20 raising the question of their relationship and clinical significance. To understand the potential relationship of HA+ granulomas with the occurrence of acute local reactions (ALRs), we evaluated the synovial tissue of OA patients undergoing total knee replacement that had previously been treated with hylan G-F 20 (n = 101) or had not been treated (n = 20). Granulomas were observed in nine patients, of which eight were in the hylan G-F 20 group (7.9%); HA+ granulomas were identified in six of these eight patients (5.9%). Three of the six patients with HA+ granulomas experienced an ALR within 30 days of administering an injection. Overall, we found no consistent relationship between histologically found HA+ granulomas and the occurrence of an ALR following hylan G-F 20 treatment. These microscopic granulomas were not associated with any symptoms and likely have little clinical significance. The low occurrence of granulomas and/or ALRs should not preclude use of hylan G-F 20 for the treatment of knee pain associated with OA.

Characterization of the kinase domain of the ephrin-B3 receptor tyrosine kinase using a scintillation proximity assay.

We have characterized a recombinantly expressed N-terminally tagged GST fusion of the tyrosine kinase domain of human EphB3. The EphB3 kinase domain was shown to phosphorylate a group of synthetic tyrosine-containing peptides derived from a proprietary biotinylated kinase-biased peptide substrate library. In addition, the enzyme activity was stimulated by the divalent cation, manganese, and inhibited by addition of magnesium. The most active tyrosine-containing peptide, a biotinylated 49-mer, displayed saturation kinetics with an apparent K(m) of approximately 0.4 microM. The apparent K(m) for ATP was determined to be approximately 3 microM. The kinetics of the reaction was linear from concentrations of enzyme of 0.5 to 2 nM, and at or below the K(m) concentrations of the two substrates for at least 2 h at room temperature. Moreover, the tryrosine kinase inhibitor, PP2, produced an IC(50) of roughly 0.8 microM. In addition, the enzyme tolerated the solvent DMSO and was stable to multiple freeze/thaw cycles. Stability of the enzyme at 4 degrees C storage was seen out to 6 h with an approximately 50% reduction of activity by 24 h. Formatting the assay in a 384-well microtiter plate produced good uniformity of signal at 100% inhibition, 50% inhibition, and no inhibition. The coefficient of variance was at or below 10% with a signal-to-background ratio of approximately 24 and a z value of 0.72. Collectively, these results showed the ability to configure a robust HTS for a truncated recombinantly expressed family member of the Ephrin tyrosine kinases.