Hussain M, Daignault S, Agarwal N, Grivas PD, Siefker-Radtke AO, et al.
Cancer •
Epidermal growth factor receptor overexpression is associated with poor outcomes in urothelial carcinoma (UC). Cetuximab (CTX) exhibited an antitumor effect in in vivo UC models. The efficacy of gemcitabine/cisplatin (GC) with or without CTX in patients with advanced UC was evaluated. Patients with advanced UC, measurable disease, and adequate organ function were randomized 1:2 to cisplatin (70 mg/m(2) ) on day 1 plus gemcitabine (1000 mg/m(2) ) on days 1, 8, and 15 (arm A) or GC plus CTX (500 mg/m(2) ) on days 1 and 15 (arm B). The primary endpoint was the overall response rate. The secondary endpoints were the response duration, safety, progression-free survival, overall survival, determination of whether or not CTX sensitized nonresponders to GC, and exploratory biomarker analysis. The accrual targets were 27 and 54 patients for the 2 arms, respectively. The overall response rate was reported by arm with binomial confidence intervals (CIs). Kaplan-Meier methods were used for time-to-event endpoints. Eighty-eight eligible patients were randomized; 87 were toxicity-evaluable, and 85 were response-evaluable. The overall response rates were 57.1% for arm A (95% CI = 37%-76%) and 61.4% for arm B (95% CI = 48%-74%). The median progression-free survival times were 8.5 months for arm A (95% CI = 5.7-10.4 months) and 7.6 months for arm B (95% CI = 6.1-8.7 months). The median overall survival times were 17.4 months for arm A (95% CI = 12.8 months to unreached) and 14.3 months for arm B (95% CI = 11.6-22.2 months). The most common grade 3/grade 4 adverse events in both arms were myelosuppression and nausea. Thromboembolism, acneiform rash, fatigue, pain, hypersensitivity reactions, elevated transaminases, hyponatremia, and hypomagnesemia were more common in arm B; 3 grade 5 adverse events occurred in arm B. The presence of primary disease significantly correlated with thromboembolism. An increased soluble E-cadherin level after cycle 2 correlated with a higher risk of death. GC plus CTX was feasible but was associated with more adverse events and no improvements in outcomes.
Farley J, Sill MW, Birrer M, Walker J, Schilder RJ, et al.
Gynecologic oncology •
The purpose of this study was to evaluate the safety and efficacy of cetuximab (C225), an antibody that inhibits epidermal growth factor receptor (EGFR) activity, with cisplatin and to explore associations between EGFR protein expression with patient demographics or clinical outcome. Women with advanced, persistent, or recurrent carcinoma of the cervix were eligible. The women received cisplatin at 30mg/m(2) on days 1 and 8 with a loading dose of cetuximab at 400mg/m(2) followed by 250mg/m(2) on days 1, 8, and 15 in a 21day cycle. Adverse events were assessed with CTCAE v 3.0. Primary measure of efficacy was tumor response by RECIST. The study was stratified by prior chemotherapy (CT). EGFR protein expression in pre-treatment tumor was analyzed by immunohistochemistry. Between September 2004 and March 2008, 76 patients were enrolled. Of these, 69 were eligible and evaluable; 44 (64%) received prior chemotherapy. There were 4 responses in each group, prior chemotherapy and no chemotherapy, 9% and 16%, respectively. Grade 4 toxicities included anemia (1), allergy (1), metabolic (1), and vascular (1). The most common grade 3 toxicities were metabolic (15), dermatologic (8), fatigue (6), and gastrointestinal (6). EGFR protein was expressed in 47/48 (98%) of tumors analyzed with a median cellular expression of 81%. Exploratory analyses revealed a trend between the percentage of cells expressing EGFR protein and PFS (hazard ratio=1.76, 95% confidence interval=0.96-3.21). The combination of cetuximab with cisplatin was adequately tolerated but did not indicate additional benefit beyond cisplatin therapy.
This phase II trial assessed the activity and tolerability of cetuximab (C225, Erbitux) in combination with carboplatin in patients with relapsed platinum-sensitive ovarian or primary peritoneal carcinoma. Patients were to receive combination therapy with cetuximab (initial dose of 400 mg/m2 intravenously on cycle 1, day 1, followed by weekly infusions of 250 mg/m2) and carboplatin (AUC of 6 on day 1 and every 3 weeks). The primary objectives of this trial were to estimate the anti-tumor activity and adverse events of this combination therapy. Immunohistochemical expression of EGFR was evaluated in tumor specimens from patients enrolled in this trial. Of the 29 patients, 28 (97%) were eligible and evaluable for analysis of the efficacy and toxicity of cetuximab administered in combination with carboplatin. Of the evaluable entries, 26 had EGFR-positive tumors and the response rate in this group of patients was as follows: 9 demonstrated an objective response (3 CR; 6 PR) and 8 had stable disease. The response rate did not meet criteria for opening a second stage of accrual. The median time to progression was 9.4+ months (range: .9-22.2+). The most commonly observed adverse events were dermatologic toxicity (grade 3 in 32%), thrombocytopenia (grade 3 in 14%), and hypersensitivity reactions (grade 3 and 4 in 18%). Cetuximab administered in combination with carboplatin had modest activity in screened patients with EGFR-positive, relapsed platinum-sensitive ovarian or primary peritoneal carcinoma. Cetuximab was associated with an acneiform rash in a majority of patients and occasional serious hypersensitivity reactions.
The assembly of complex structures bearing the H determinant was examined by characterizing the specificities of a cloned blood group H gene-specified alpha 1,2-L-fucosyltransferase (FT) toward a variety of sulfated, sialylated, or fucosylated Gal beta 1,3/4GlcNAc beta- or Gal beta 1,3GalNAc alpha-based acceptor structures. (a) As compared to the basic type 2, Gal beta 1,4GlcNAc beta-(K(m) = 1.67 mM), the basic type 1 was 137% active (K(m) = 0.83 mM). (b) On C-6 sulfation of Gal, type 1 became 142.1% active and type 2 became 223.0% active (K(m) = 0.45 mM). (c) On C-6 sulfation of GlcNAc, type 2 showed 33.7% activity. (d) On C-3 or C-4 fucosylation of GlcNAc, both types 1 and 2 lost activity. (e) Type 1 showed 70.8% and 5.8% activity, respectively, on C-6 and C-4 O-methylation of GlcNAc. (f) Type 1 retained 18.8% activity on alpha 2,6-sialylation of GlcNAc. (g) Terminal type 1 or 2 of extended chain had lower activity. (h) With Gal in place of GlcNAc in type 1, the activity became 43.2%. (i) Compounds with terminal alpha 1,3-linked Gal were inactive. (j) Gal beta 1,3GalNAc alpha- (the T-hapten) was approximately 0.4-fold as active as Gal beta 1,4GlcNAc beta-. (k) C-6 sulfation of Gal on the T-hapten did not affect the acceptor activity. (l) C-6 sulfation of GalNAc decreased the activity to 70%, whereas on C-6 sulfation of both Gal and GalNAc the T-hapten lost the acceptor ability. (m) C-6 sialylation of GalNAc also led to inactivity. (n) beta 1,6 branching from GalNAc of the T-hapten by a GlcNAc residue or by units such as Gal beta 1, 4GlcNAc-, Gal beta 1,4(Fuc alpha 1,3)GlcNAc-, or 3-sulfoGal beta 1,4GlcNAc- resulted in 111.9%, 282.8%, 48.3%, and 75.3% activities, respectively. (o) The enhancement of enzyme affinity by a sulfo group on C-6 of Gal was demonstrated by an increase (approximately 5-fold) in the K(m) for Gal beta 1,4GlcNAc beta 1,6(Gal beta 1,3)GalNAc alpha-O-Bn in presence of 6-sulfoGal beta 1,- 4GlcNAc beta-O-Me (3.0 mM). (p) Among the two sites in Gal beta 1, 4GlcNAc beta 1,6(Gal beta 1,3) GalNAc alpha-O-Bn, the enzyme had a higher affinity ( > 3-fold) for the Gal linked to GlcNAc. (q) With respect to Gal beta 1,- 3GlcNAc beta-O-Bn (3.0 mM), fetuin triantennary asialo glycopeptide (2.4 mM), bovine IgG diantennary glycopeptide (2.8 mM), asialo Cowper's gland mucin (0.06 mM), and the acrylamide copolymers (0.125 mM each) containing Gal beta 1,3GlcNAc beta-, Gal beta 1,3(6-sulfo)GlcNAc beta-, Gal beta 1,3GalNAc alpha-, Gal beta 1,3Gal beta-, or Gal alpha 1,3Gal beta- units were 153.6%, 43.0%, 6.2%, 52.5%, 94.9%, 14.7%, 23.6%, and 15.6% active, respectively. (r) Fucosylation by alpha 1,2-L-FT of the galactosyl residue which occurs on the antennary structure of the bovine IgG glycopeptide was adversely affected by the presence of an alpha 1,6-L-fucosyl residue located on the distant glucosaminyl residue that is directly attached to the asparagine of the protein backbone. This became evident from the 4-fold activity of alpha 1,2-L-FT toward bovine IgG glycopeptide after approximately 5% removal of alpha 1,6-linked Fuo.
Synthesis of two trisaccharides and a tetrasaccharide, namely, alpha-Gal-(1-->3)-beta-Gal-(1-->3)-GlcNAc-beta-OBn (6), alpha-Gal-(1-->3)-beta-Gal-(1-->4)-GlcNAc-beta-OBn (9) and alpha-Gal-(1-->3)-beta-Gal-(1-->4)-GlcNAc-beta-(1-->6)-GalNAc- alpha-OBn (19) was accomplished through development and utilization of a key alpha-galactosyl donor, methyl 2,3,4,6-tetra-O-(4- methoxybenzyl)-1-thio-beta-D-galactopyranoside (1).
