Vemurafenib in patients with BRAF(V600) mutated metastatic melanoma: an open-label, multicentre, safety study.

BACKGROUND: The orally available BRAF kinase inhibitor vemurafenib, compared with dacarbazine, shows improved response rates, progression-free survival (PFS), and overall survival in patients with metastatic melanoma that has a BRAF(V600) mutation. We assessed vemurafenib in patients with advanced metastatic melanoma with BRAF(V600) mutations who had few treatment options. METHODS: In an open-label, multicentre study, patients with untreated or previously treated melanoma and a BRAF(V600) mutation received oral vemurafenib 960 mg twice a day. The primary endpoint was safety. All analyses were done on the safety population, which included all patients who received at least one dose of vemurafenib. This report is the third interim analysis of this study. This study is registered with ClinicalTrials.gov, number NCT01307397. FINDINGS: Between March 1, 2011, and Jan 31, 2013, 3226 patients were enrolled in 44 countries. 3222 patients received at least one dose of vemurafenib (safety population). At data cutoff, 868 (27%) patients were on study treatment and 2354 (73%) had withdrawn, mainly because of disease progression. Common adverse events of all grades included rash (1592 [49%]), arthralgia (1259 [39%]), fatigue (1093 [34%]), photosensitivity reaction (994 [31%]), alopecia (826 [26%]), and nausea (628 [19%]). 1480 (46%) patients reported grade 3 or 4 adverse events, including cutaneous squamous cell carcinoma (389 [12%]), rash (155 [5%]), liver function abnormalities (165 [5%]), arthralgia (106 [3%]), and fatigue (93 [3%]). Grade 3 and 4 adverse events were reported more frequently in patients aged 75 years and older (n=257; 152 [59%, 95% CI 53-65] and ten [4%, 2-7], respectively) than in those younger than 75 years (n=2965; 1286 [43%, 42-45] and 82 [3%, 2-3], respectively). INTERPRETATION: Vemurafenib safety in this diverse population of patients with BRAF(V600) mutated metastatic melanoma, who are more representative of routine clinical practice, was consistent with the safety profile shown in the pivotal trials of this drug. FUNDING: F Hoffmann-La Roche.

Phase II trial of continuous once-daily dosing of sunitinib as first-line treatment in patients with metastatic renal cell carcinoma.

BACKGROUND: Sunitinib at 50 mg/day on the 4-weeks-on-2-weeks-off schedule is the current approved regimen for advanced/metastatic renal cell carcinoma (mRCC). Escudier et al reported that continuous, once-daily dosing with sunitinib 37.5 mg had a manageable safety profile and significant antitumor activity as second-line mRCC therapy. In this prospective, multicenter, phase II study, we evaluated the activity of continuous once-daily dosing with sunitinib 37.5 mg as first-line mRCC treatment. METHODS: One hundred nineteen treatment-naive patients with measurable mRCC received sunitinib. The primary endpoint was objective response; secondary endpoints included progression-free survival (PFS), safety, pharmacokinetic measurements, exploration of response biomarkers, and patient reported outcomes (PRO). RESULTS: Objective response rate (ORR) was 35.3%; median response duration was 10.4 months; 36% of patients had stable disease ≥12 weeks. Median PFS at 1 year was 9 months, and 1-year survival probability was 67.8%. The most common any-grade treatment-related adverse events (AEs) were diarrhea (50%) and hand-foot syndrome (43%); the most common grade 3-4 treatment-related AEs were hand-foot syndrome (13%), neutropenia (11%), and diarrhea (9%). Steady-state pharmacokinetics were reached within 3 weeks, with no disproportionate accumulation of sunitinib or its active metabolite throughout the study. No significant correlations between trough drug, active metabolite, or soluble protein levels and clinical response were observed. PRO was largely maintained, although fatigue appeared to worsen after treatment started, with improvement over time. CONCLUSIONS: Continuous once-daily dosing with sunitinib 37.5 mg was active with a manageable safety profile as first-line mRCC therapy, making this a feasible alternative dosing regimen.

A role for pabAB, a p-aminobenzoate synthase gene of Streptomyces venezuelae ISP5230, in chloramphenicol biosynthesis.

Mutagenesis of Streptomyces venezuelae ISP5230 and selection for P-aminobenzoic acid-dependent growth in the presence of sulfanilamide yielded pab mutants (VS519 and VS620) that continued to produce chloramphenicol (Cm), although with increased medium dependence. Transforming the mutants with pDQ102 or pDQ103, which carried a pab-complementing fragment from S. venezuelae ISP5230 in alternative orientations, restored uniformly high Cm production in VS620, but did not alter the medium dependence of Cm production in VS519. The cloned S. venezuelae DNA fragment was subcloned and trimmed to the minimum size conferring pab complementation. The resulting 2.8 kb BamHl-Sacl fragment was sequenced. Codon preference analysis showed one complete ORF encoding a polypeptide of 670 amino acids. Comparison of the deduced amino acid sequence with database proteins indicated that the N- and C-terminal regions resembled PabA and PabB, respectively, of numerous bacteria. The gene product showed overall sequence similarity to the product of a fused pabAB gene associated with secondary metabolism in Streptomyces griseus. Insertion of an apramycin resistance gene into pabAB cloned in a segregationally unstable vector and replacement of the S. venezuelae chromosomal pabAB with the disrupted copy lowered sulfanilamide resistance from 25 to 5 micrograms mL-1 and blocked Cm production.