Nick Teoh

Epratuzumab (humanised anti-CD22 antibody) in primary Sjogren's syndrome: an open-label phase I/II study.

This open-label, phase I/II study investigated the safety and efficacy of epratuzumab, a humanised anti-CD22 monoclonal antibody, in the treatment of patients with active primary Sjögrens syndrome (pSS). Sixteen Caucasian patients (14 females/2 males, 33–72 years) were to receive 4 infusions of 360 mg/m2 epratuzumab once every 2 weeks, with 6 months of follow-up. A composite endpoint involving the Schirmer-I test, unstimulated whole salivary flow, fatigue, erythrocyte sedimentation rate (ESR), and immunoglobulin G (IgG) was devised to provide a clinically meaningful assessment of response, defined as a ≥20% improvement in at least two of the aforementioned parameters, with ≥20% reduction in ESR and/or IgG considered as a single combined criterion. Fourteen patients received all infusions without significant reactions, 1 patient received 3, and another was discontinued due to a mild acute reaction after receiving a partial infusion. Three patients showed moderately elevated levels of Human anti-human (epratuzumab) antibody not associated with clinical manifestations. B-cell levels had mean reductions of 54% and 39% at 6 and 18 weeks, respectively, but T-cell levels, immunoglobulins, and routine safety laboratory tests did not change significantly. Fifty-three percent achieved a clinical response (at ≥20% improvement level) at 6 weeks, with 53%, 47%, and 67% responding at 10, 18, and 32 weeks, respectively. Approximately 40%–50% responded at the ≥30% level, while 10%–45% responded at the ≥50% level for 10–32 weeks. Additionally, statistically significant improvements were observed in fatigue, and patient and physician global assessments. Further, we determined that pSS patients have a CD22 over-expression in their peripheral B cells, which was downregulated by epratuzumab for at least 12 weeks after the therapy. Thus, epratuzumab appears to be a promising therapy in active pSS, suggesting that further studies be conducted.

Multicenter Phase II Trial of Immunotherapy With the Humanized Anti-CD22 Antibody, Epratuzumab, in Combination With Rituximab, in Refractory or Recurrent Non-Hodgkin's Lymphoma

PURPOSE A multicenter, single-arm study examining efficacy and toxicity of epratuzumab combined with rituximab was conducted in patients with recurrent or refractory non-Hodgkins lymphoma. PATIENTS AND METHODS Sixty-five patients were enrolled; 34 patients with follicular lymphoma (FL), 15 patients with diffuse large B-cell lymphoma (DLBCL), and 16 patients with other lymphomas. The patients had received a median of two prior therapies (range, 1 to 4); 23% had received rituximab. Epratuzumab was given at 360 mg/m2 intravenously over 60 minutes followed by infusion of 375 mg/m2 rituximab, weekly for 4 consecutive weeks. RESULTS Combination therapy was well tolerated without greater toxicity than rituximab alone. The objective response (OR) rate was 47% (30 of 64) in assessable patients (46%; 30 of 65 in all patients), being highest in FL (64%; 21 of 33) and DLBCL (47%; seven of 15), and with 24% (eight of 33) and 33% (five of 15) achieving complete response (CR) or complete response unconfirmed (CRu) in these two groups, respectively. Two of six patients with marginal zone lymphoma responded to treatment (one CR). There was a trend for the response rates to be higher in patients with low prognostic index scores (statistically significant with respect to the Follicular Lymphoma International Prognostic Index score in FL patients), with 12 FL patients and three DLBCL patients in groups 0 to 1 having OR (CR/CRu) rates of 83% (33%) and 100% (100%), respectively. The median duration of response was 16 months for FL, with five patients currently progression free for 18 months to 30 months, and 6 months for DLBCL, with two patients currently progression free for 12 months and 18 months. CONCLUSION Epratuzumab combined with rituximab was well tolerated, demonstrating promising antilymphoma activity that warrants additional study.

Durable complete responses from therapy with combined epratuzumab and rituximab: final results from an international multicenter, phase 2 study in recurrent, indolent, non-Hodgkin lymphoma.

In this international, multicenter trial, the authors evaluated rituximab (anti‐CD20) plus epratuzumab (anti‐CD22) in patients with postchemotherapy relapsed/refractory, indolent non‐Hodgkin lymphoma (NHL), including long‐term efficacy.

High Rates of Durable Responses With Anti-CD22 Fractionated Radioimmunotherapy: Results of a Multicenter, Phase I/II Study in Non-Hodgkin's Lymphoma

PURPOSE Fractionated radioimmunotherapy targeting CD22 may substantially improve responses and outcome in non-Hodgkins lymphoma (NHL). PATIENTS AND METHODS A multicenter trial evaluated two or three weekly infusions of yttrium-90 ((90)Y) epratuzumab tetraxetan (humanized anti-CD22 antibody) in 64 patients with relapsed/refractory NHL, including 17 patients who underwent prior autologous stem-cell transplantation (ASCT). Objective (OR) and complete responses (CR/complete response unconfirmed [CRu]), as well as progression-free survival (PFS), were determined. RESULTS At the maximum total (90)Y dose of 45 mCi/m(2) (1,665 MBq/m(2)), grade 3 to 4 hematologic toxicities were reversible to grade 1 in patients with less than 25% bone marrow involvement. The overall OR rate and median PFS for all 61 evaluable patients was 62% (CR/CRu, 48%) and 9.5 months, respectively. Patients without prior ASCT obtained high OR rates of 71% (CR/CRu, 55%) across all NHL subtypes and (90)Y doses, even in poor-risk categories (refractory to last anti-CD20-containing regimen, 73% [CR/CRu, 60%]; bulky disease: 71% [CR/CRu, 43%]). Patients with prior ASCT received lower doses, but achieved an OR rate of 41% (CR/CRu, 29%). For patients with follicular lymphoma (FL), OR rates and median PFS increased with total (90)Y-dose, reaching 100% (CR/CRu, 92%) and 24.6 months, respectively, at the highest dose levels (> 30 mCi/m(2) total (90)Y-dose [1,110 MBq/m(2)]). Further, patients with FL refractory to prior anti-CD20-containing regimens achieved 90% (nine of 10 patients) OR and CR/CRu rates and a median PFS of 21.5 months. CONCLUSION Fractionated anti-CD22 radioimmunotherapy provides high total doses of (90)Y, yielding high rates of durable CR/CRus in relapsed/refractory NHL, resulting in 20 mCi/m(2) x 2 weeks as the recommended dose for future studies.

Subcutaneous injections of low-dose veltuzumab (humanized anti-CD20 antibody) are safe and active in patients with indolent non-Hodgkin’s lymphoma

Background Subcutaneous injections of anti-CD20 antibodies may offer benefits to both patients and the healthcare system for treatment of B-cell malignancies. Design and Methods A pilot study was undertaken to evaluate the potential for subcutaneous dosing with 2nd generation anti-CD20 antibody veltuzumab in patients with CD20+ indolent non-Hodgkin’s lymphoma. Patients with previously untreated or relapsed disease received 4 doses of 80, 160, or 320 mg veltuzumab injected subcutaneously every two weeks. Responses were assessed by computed tomography scans, with other evaluations including adverse events, safety laboratories, B-cell blood levels, serum veltuzumab levels, and human anti-veltuzumab antibody (HAHA) titers. Results Seventeen patients (14 follicular lymphoma; 13 stage III or IV disease; 5 treatment-naive) completed treatment with only occasional, mild-moderate, transient injection reactions and no other safety issues. Subcutaneous veltuzumab demonstrated a slow release pattern over several days, achieving a mean Cmax of 19, 25 and 63 μg/mL at 80, 160, and 320 mg doses for a total of 4 administrations, respectively. Depletion of circulating B cells occurred after the first injection. The objective response rate (partial responses plus complete responses plus complete responses unconfirmed) was 47% (8/17) with a complete response/complete response unconfirmed rate of 24% (4/17); 4 of 8 objective responses continued for 60 weeks or more. All serum samples evaluated for human anti-veltuzumab antibody were negative. Conclusions Subcutaneous injections of low-dose veltuzumab are convenient, well tolerated, and capable of achieving sustained serum levels, B-cell depletion, and durable objective responses in indolent non-Hodgkin’s lymphoma. (Clinicaltrials.gov identifier: NCT00546793)

Treatment of Advanced Pancreatic Carcinoma with 90Y-Clivatuzumab Tetraxetan: A Phase I Single-Dose Escalation Trial

Purpose: Humanized antibody hPAM4 specifically binds a mucin glycoprotein expressed in pancreatic adenocarcinomas. This phase I study evaluated a single dose of 90Y-clivatuzumab tetraxetan (90Y-labeled hPAM4) in patients with advanced pancreatic cancer. Experimental Design: Twenty-one patients (4 stage III; 17 stage IV) received 111In-hPAM4 for imaging and serum sampling before 90Y-hPAM4. Study procedures evaluated adverse events, safety laboratories, computed tomography (CT) scans, biomarkers, pharmacokinetics, radiation dosimetry, and immunogenicity (HAHA). Results:111In-hPAM4 showed normal biodistribution with radiation dose estimates to red marrow and solid organs acceptable for radioimmunotherapy and with tumor targeting in 12 patients. One patient withdrew before 90Y-hPAM4; otherwise, 20 patients received 90Y doses of 15 (n = 7), 20 (n = 9), and 25 mCi/m2 (n = 4). Treatment was well tolerated; the only significant drug-related toxicities were (NCI CTC v.3) grade 3 to 4 neutropenia and thrombocytopenia increasing with 90Y dose. There were no bleeding events or serious infections, and most cytopenias recovered to grade 1 within 12 weeks. Three patients at 25 mCi/m2 encountered dose-limiting toxicity with grade 4 cytopenias more than 7 days, establishing 20 mCi/m2 as the maximal tolerated 90Y dose. Two patients developed HAHA of uncertain clinical significance. Most patients progressed rapidly and with CA19-9 levels increasing within 1 month of therapy, but 7 remained progression-free by CT for 1.5 to 5.6 months, including 3 achieving transient partial responses (32%–52% tumor diameter shrinkage). Conclusion:90Y-Clivatuzumab tetraxetan was well tolerated with manageable hematologic toxicity at the maximal tolerated 90Y dose, and is a potential new therapeutic for advanced pancreatic cancer. Clin Cancer Res; 17(12); 4091–100. ©2011 AACR.