Momelotinib in Myelofibrosis Patients With Thrombocytopenia: Post Hoc Analysis From Three Randomized Phase 3 Trials

The oral activin A receptor type I, Janus kinase 1 (JAK1), and JAK2 inhibitor momelotinib demonstrated symptom, spleen, and anemia benefits in intermediate- and high-risk myelofibrosis (MF). Post hoc analyses herein evaluated the efficacy and safety of momelotinib in patients with MF and thrombocytopenia (platelet counts <100 × 109/L) from randomized phase 3 studies: MOMENTUM (momelotinib versus danazol; JAK inhibitor experienced); SIMPLIFY-1 (momelotinib versus ruxolitinib; JAK inhibitor naïve); and SIMPLIFY-2 (momelotinib versus best available therapy; JAK inhibitor experienced); these studies were not statistically powered to assess differences in thrombocytopenic subgroups, and these analyses are descriptive. The treatment effect of momelotinib versus ruxolitinib on week 24 response rates (spleen volume reduction ≥35%/Total Symptom Score reduction ≥50%/transfusion independence) was numerically comparable or better in thrombocytopenic patients versus the overall JAK inhibitor naive population; rates were preserved with momelotinib in thrombocytopenic patients but attenuated with ruxolitinib (momelotinib: 27%/28%/67% overall versus 39%/35%/61% in thrombocytopenic group; ruxolitinib: 29%/42%/49% overall versus 0%/22%/39% in thrombocytopenic group, respectively). In contrast to ruxolitinib, momelotinib maintained high dose intensity throughout the treatment. In the JAK inhibitor experienced population, thrombocytopenic patients had the following: (1) numerically higher symptom and transfusion independence response rates with momelotinib than in control arms; and (2) preserved spleen, symptom, and transfusion independence response rates with momelotinib relative to the overall study populations. The safety profile of momelotinib in thrombocytopenic patients was also consistent with the overall study population. In summary, momelotinib represents a safe and effective treatment option for patients with MF and moderate-to-severe thrombocytopenia.

Overall survival in the SIMPLIFY-1 and SIMPLIFY-2 phase 3 trials of momelotinib in patients with myelofibrosis

Janus kinase inhibitors (JAKi) approved for myelofibrosis provide spleen and symptom improvements but do not address anemia, a negative prognostic factor. Momelotinib, an inhibitor of ACVR1/ALK2, JAK1 and JAK2, demonstrated activity against anemia, symptoms, and splenomegaly in the phase 3 SIMPLIFY trials. Here, we report mature overall survival (OS) and leukemia-free survival (LFS) from both studies, and retrospective analyses of baseline characteristics and efficacy endpoints for OS associations. Survival distributions were similar between JAKi-naïve patients randomized to momelotinib, or ruxolitinib then momelotinib, in SIMPLIFY-1 (OS HR = 1.02 [0.73, 1.43]; LFS HR = 1.08 [0.78, 1.50]). Two-year OS and LFS were 81.6% and 80.7% with momelotinib and 80.6% and 79.3% with ruxolitinib then momelotinib. In ruxolitinib-exposed patients in SIMPLIFY-2, two-year OS and LFS were 65.8% and 64.2% with momelotinib and 61.2% and 59.7% with best available therapy then momelotinib (OS HR = 0.98 [0.59, 1.62]; LFS HR = 0.97 [0.59, 1.60]). Baseline transfusion independence (TI) was associated with improved survival in both studies (SIMPLIFY-1 HR = 0.474, p = 0.0001; SIMPLIFY-2 HR = 0.226, p = 0.0005). Week 24 TI response in JAKi-naïve, momelotinib-randomized patients was associated with improved OS in univariate (HR = 0.323; p < 0.0001) and multivariate (HR = 0.311; p < 0.0001) analyses. These findings underscore the importance of achieving or maintaining TI in myelofibrosis, supporting the clinical relevance of momelotinib’s pro-erythropoietic mechanism of action, and potentially informing treatment decision-making.

Safety and Efficacy of a DNA Oligonucleotide Therapy in Patients with Relapsed or Refractory Diffuse Large B-Cell Lymphoma

BACKGROUND

PNT2258 is a liposomal formulation that encapsulates multiple copies of PNT100, a native, chemically unmodified, 24-base DNA oligonucleotide designed to target the regulatory region upstream of the B-cell lymphoma 2 (BCL2) gene.

METHODS

This phase II, multicenter, single-arm, open-label, 2-stage design study investigated the single-agent activity of PNT2258 in patients with relapsed/refractory DLBCL. Initially, patients had to have a performance status (PS) of ≤2 and prior exposure to CD20-targeted therapy, an alkylating agent, and a steroid with no upper limit. Criteria were modified to PS of 0 or 1 and at least 1 to ≤3 prior therapies (identified as the target population) after observing an initially high frequency of rapid disease progression in patients with extensive prior therapies or poor PS.

RESULTS

The study was stopped early following an interim analysis, despite surpassing the protocol predetermined futility boundary, because the ORR was below the expectations of response in an evolving DLBCL treatment landscape. The final analysis included all 45 enrolled patients and demonstrated an ORR of 11%. In the response evaluable subset (n = 26), defined as patients in the target population with exposure to ≥8 doses of PNT2258 within the first 35 days and evaluable baseline/post-baseline scans, the ORR was 19%. The most common adverse events were fatigue (44%), nausea (42%), diarrhea (40%), pyrexia (36%), anemia (32%), and vomiting (27%).

CONCLUSIONS

PNT2258 was well-tolerated in a chemotherapy refractory DLBCL population. Despite demonstration of single-agent activity, ORR was lower than acceptable for further new therapy development.

A Phase 2 Study of PNT2258 for Treatment of Relapsed or Refractory B-Cell Malignancies

BACKGROUND

PNT2258 consists of a native, chemically unmodified, 24-base DNA oligonucleotide designed to target the regulatory region upstream of the BCL2 gene, delivered in a protective liposome. Derangement of BCL2-regulated control mechanisms is a defining characteristic of certain malignancies, and it was hypothesized that the oligonucleotide would promote anticancer activity via suppression of BCL2 transcription.

METHODS

PNT2258 was evaluated in this, multicenter, nonrandomized, open-label Phase 2 study in 13 participants with relapsed/refractory B-cell malignancies to investigate potential antitumor activity and safety. Participants with follicular lymphoma, diffuse large B-cell lymphoma, mantle cell lymphoma, or chronic lymphocytic leukemia received intravenous PNT2258 120 mg/m² on Days 1 to 5 of a 21-day cycle for up to 8 cycles, followed by 100 mg/m² on Days 1 to 2 of a 28-day cycle until study withdrawal.

RESULTS

All 13 participants were treated with PNT2258 monotherapy and evaluable for response and safety and tolerability. The overall response rate was 53.8% (7/13; 95% confidence interval [CI], 25.1%-80.8%). Median duration of response was 23.4 months (range, 3, 31.5). The disease control rate of participants with stable disease or better was 84.6% (95% CI, 54.6%-98.1%). The most frequently (≥50%) observed adverse events (AEs) were nausea, chills, diarrhea, fatigue, headache, vomiting, and back pain. Hypertension (30.8%) and diarrhea (23.1%) were the most frequent grade ≥3 AEs. No deaths were observed.

CONCLUSION

Clinically meaningful and durable activity with an acceptable safety profile was observed in participants with relapsed/refractory B-cell malignancies who received single-agent PNT2258.

TRIAL REGISTRATION

NCT01733238, first posted 26-Nov-2012. https://clinicaltrials.gov/ct2/show/NCT01733238.

Lugano 2014 criteria for assessing FDG-PET/CT in lymphoma: an operational approach for clinical trials

An operationalized workflow paradigm is presented and validated with pilot subject data. This approach is reproducible with a high concordance rate between individual readers (kappa 0.73 [confidence interval 0.59-0.87; P=<0.0001]) using a 5-point scale to assess [18F] labeled fluorodeoxyglucose metabolic activity in lymphomatous lesions. These results suggest an operationally practical 5-point scale workflow paradigm for potential use in larger clinical trials evaluating lymphoma therapeutics.

Design and rationale of FOCUS (PX-171-011): a randomized, open-label, phase 3 study of carfilzomib versus best supportive care regimen in patients with relapsed and refractory multiple myeloma (R/R MM)

Background

Carfilzomib is a next-generation proteasome inhibitor with single-agent activity in patients with relapsed and refractory multiple myeloma (R/R MM). In PX-171-003-A1, a single-arm phase 2 study of carfilzomib monotherapy in heavily pretreated patients, the overall response rate was 23.7%, 37% of patients achieved ≥ minimal response and median overall survival (OS) was 15.6 months. Based on this study, carfilzomib was recently approved by the US Food and Drug Administration for the treatment of R/R MM. Herein we describe the trial design and rationale for a phase 3 randomized study, FOCUS (CarFilzOmib for AdvanCed Refractory MUltiple Myeloma European Study), being conducted to compare OS after treatment with single-agent carfilzomib to best supportive care (BSC) regimen in R/R MM.

Methods

Patients must have received ≥3 prior regimens, must be responsive to at least 1 line of therapy, and be refractory to their most recent therapy. Eligible patients are randomized 1:1 to receive either carfilzomib (28-day cycles at 20 mg/m² IV on Days 1–2 of Cycle 1, escalating to 27 mg/m² IV on Days 8, 9, 15, and 16 and continuing at 27 mg/m² through Cycle 9 and Days 1, 2, 15, and 16 ≥ Cycle 10) or an active BSC regimen (corticosteroid treatment of prednisolone 30 mg, dexamethasone 6 mg, or equivalent every other day with optional cyclophosphamide 50 mg PO once daily). Patients will continue treatment until disease progression, unacceptable toxicity, or treatment discontinuation and will then enter long-term follow-up for survival. The primary endpoint is OS and secondary endpoints include progression-free survival, overall response rate, and safety. Disease assessments will be determined according to the International Myeloma Working Group Uniform Response Criteria with minimal response per European Blood and Marrow Transplantation Group criteria.

Conclusions

This phase 3 trial will provide more rigorous data for carfilzomib, as this is the first carfilzomib study with OS as the primary endpoint and will not be confounded by crossover and will provide more robust secondary response and safety results that will add to the data set from prior phase 2 studies. FOCUS will facilitate regulatory approvals around the world and expand treatment options for patients with R/R MM.

Trial registration

EudraCT No. 2009-016840-38; NCT01302392.

Clinical implications of pathophysiological and demographic covariates on the population pharmacokinetics of trastuzumab emtansine, a HER2-targeted antibody-drug conjugate, in patients with HER2-positive metastatic breast cancer

Trastuzumab emtansine (T-DM1) is a HER2-targeted antibody-drug conjugate in development for treatment of HER2-positive cancers. T-DM1 has been tested as a single agent in a phase I and 2 phase II studies of patients with heavily pretreated metastatic breast cancer (MBC), with the maximum tolerated dose established at 3.6 mg/kg intravenously for every-3-week dosing. The authors present results from the population pharmacokinetics analysis for T-DM1. Population pharmacokinetics for T-DM1 were characterized using a clinical database of 273 patients from the 3 studies. Pharmacokinetics was best described by a linear 2-compartment model. Population estimates (interindividual variability [IIV]) for pharmacokinetic parameters were clearance, 0.7 L/d (21.0%); central compartment volume (V(c)), 3.33 L (13.2%); peripheral compartment volume (V(p)), 0.89 L (50.4%); and intercompartmental clearance, 0.78 L/d. Body weight, albumin, tumor burden, and aspartate aminotransferase levels were identified as statistically significant covariates accounting for interindividual variability in T-DM1 pharmacokinetics, with body weight having a greater effect on IIV of clearance and V(c) than other covariates. T-DM1 exposure was relatively consistent across the weight range following body weight-based dosing. This analysis suggests no further T-DM1 dose adjustments are necessary in heavily pretreated patients with MBC.

Phase II study of the antibody drug conjugate trastuzumab-DM1 for the treatment of human epidermal growth factor receptor 2 (HER2)-positive breast cancer after prior HER2-directed therapy

PURPOSE

The antibody-drug conjugate trastuzumab-DM1 (T-DM1) combines the biologic activity of trastuzumab with targeted delivery of a potent antimicrotubule agent, DM1, to human epidermal growth factor receptor 2 (HER2)-overexpressing cancer cells. Based on results from a phase I study that showed T-DM1 was well tolerated at the maximum-tolerated dose of 3.6 mg/kg every 3 weeks, with evidence of efficacy, in patients with HER2-positive metastatic breast cancer (MBC) who were previously treated with trastuzumab, we conducted a phase II study to further define the safety and efficacy of T-DM1 in this patient population.

PATIENTS AND METHODS

This report describes a single-arm phase II study (TDM4258g) that assessed efficacy and safety of intravenous T-DM1 (3.6 mg/kg every 3 weeks) in patients with HER2-positive MBC who had tumor progression after prior treatment with HER2-directed therapy and who had received prior chemotherapy.

RESULTS

With a follow-up of ≥ 12 months among 112 treated patients, the objective response rate by independent assessment was 25.9% (95% CI, 18.4% to 34.4%). Median duration of response was not reached as a result of insufficient events (lower limit of 95% CI, 6.2 months), and median progression-free survival time was 4.6 months (95% CI, 3.9 to 8.6 months). The response rates were higher among patients with confirmed HER2-positive tumors (immunohistochemistry 3+ or fluorescent in situ hybridization positive) by retrospective central testing (n = 74). Higher response rates were also observed in patients whose tumors expressed ≥ median HER2 levels by quantitative reverse transcriptase polymerase chain reaction for HER2 expression, compared with patients who had less than median HER2 levels. T-DM1 was well tolerated with no dose-limiting cardiotoxicity. Most adverse events (AEs) were grade 1 or 2; the most frequent grade ≥ 3 AEs were hypokalemia (8.9%), thrombocytopenia (8.0%), and fatigue (4.5%).

CONCLUSION

T-DM1 has robust single-agent activity in patients with heavily pretreated, HER2-positive MBC and is well tolerated at the recommended phase II dose.

Safety and efficacy of erlotinib in first-relapse glioblastoma: a phase II open-label study

Erlotinib, an epidermal growth factor receptor (EGFR) tyrosine kinase inhibitor, is active in glioblastoma. We evaluated erlotinib efficacy in patients with first-relapse glioblastoma and assessed whether response was related to EGFR amplification and/or concomitant use of enzyme-inducing antiepileptic drugs (EIAEDs) in a phase II open-label study of glioblastoma patients in first relapse. Patients took erlotinib daily until progression. Starting dose was 150 mg for patients not taking EIAEDs and 300 mg for patients taking EIAEDs. Tumors were radiographically assessed every 8 weeks. Response was evaluated by investigators and confirmed by an independent radiology facility (IRF). The primary efficacy outcome was the objective response (OR) rate, according to the modified WHO criteria. Enrollment (n = 48) was terminated after a planned interim analysis due to an insufficient number of responses. The IRF confirmed 1 complete and 2 partial responses (PRs), for an OR rate of 6.3% (95% confidence interval [CI]: 1.7-17.0). Investigators determined 1 complete response and 3 PRs, median response duration of 7.0 months, 6-month progression-free survival (PFS) of 20% (95% CI: 10.0-32.4), and median survival of 9.7 months (95% CI: 5.9-11.6). Outcomes were not related to EGFR amplification or EIAED status. Diarrhea and rash were the most common adverse events (AEs); 23% of patients experienced grade 3-4 drug-related AEs. Despite the limited number of responses, 6-month PFS and median survival reached or exceeded the previously reported values for patients undergoing chemotherapy for recurrent glioblastoma. EGFR amplification was not associated with erlotinib activity. Given the large CIs and nonrandomized nature of the study, results should be interpreted cautiously.

A phase II study of trastuzumab-DM1 (T-DM1), a HER2 antibody-drug conjugate (ADC), in patients (pts) with HER2+ metastatic breast cancer (MBC): Final results

1017

Background: T-DM1 is an ADC that combines the biological activity of trastuzumab (T) with targeted delivery of a potent antimicrotubule agent, DM1, to HER2-expressing cancer cells. In a phase I study, T-DM1 was administered IV q3w to pts with HER2+ MBC who had progressed on T + chemotherapy. T-DM1 was well-tolerated at the maximum tolerated dose (MTD) of 3.6 mg/kg, with no reports of cardiac toxicity. The confirmed objective response rate (ORR) for the 9 pts with measurable disease treated at the MTD was 44%. The phase II study described here further assesses tolerability and activity of T-DM1. Methods: This was a multi-institutional, open-label, single-arm phase II study, to enroll 100 pts. All eligible pts had progressed on HER2-directed therapy and had received chemotherapy in the metastatic setting. T-DM1 was administered at 3.6 mg/kg IV q3w. Primary objectives were assessment of ORR and of safety and tolerability. Results: As of the August 29, 2008, data-cut, 112 patients had enrolled, with baseline median age 54.5 (range 33–82); ECOG PS 2 or 3, 80%; 68.7% with > 3 sites of metastatic disease; median 3 (range 1–14) prior chemotherapy agents for metastatic disease, median 76.3 weeks prior T, and 55.4% with previous lapatinib. Due to limited F/U, the median number of T-DM1 cycles received was 5 (range 1–16), and 19 of the 107 efficacy evaluable patients had only one post-baseline tumor assessment. Fifty-six pts had discontinued study treatment. With a median follow-up of 4.4 mos, there were 42 (39.3%) ORs (CR or PR), 29 (27.1%) of which have been confirmed by follow-up (F/U) imaging. Among the subgroup of pts who had either >6 months F/U or had discontinued from the study at any time (n = 76) there were 33 ORs (43.4%), 29 (38.2%) of which were confirmed by F/U imaging. The most common grade 3–4 AE was thrombocytopenia (7.1%). Updated data will be presented at the meeting, including updated ORR, 6-month clinical benefit rate, ORR by independent review, progression-free survival, and duration of response. Conclusions: T-DM1 has single-agent activity in pts with previously treated, HER2+ MBC, and is well tolerated at the recommended phase II dose.

[Table: see text]

Quantitative assessment of HER2 status and correlation with efficacy for patients (pts) with metastatic breast cancer (MBC) in a phase II study of trastuzumab-DM1 (T-DM1)

1003

Background: The antibody-drug conjugate T-DM1 combines the biological activity of trastuzumab with targeted delivery of an anti-microtubule agent (DM1) to HER-2-expressing cancer cells. This analysis examines correlation of response to T-DM1 with HER-2 status, as assessed by fluorescent in situ hybridization (FISH), immunohistochemistry (IHC), mRNA quantitative real-time polymerase chain reaction (qRT-PCR), and enzyme-linked immunosorbent assay (ELISA) (HER-2 extracellular domain [ECD]), for pts enrolled in TDM4258g, a phase II study of T-DM1 in pts with MBC. Methods: TDM4258g is an open-label, single-arm study of T-DM1 administered at 3.6 mg/kg IV q3w. Pts had progressed on HER-2-directed therapy and received chemotherapy in the metastatic setting and were HER-2 + based on local testing. Archival tissue (paraffin block or >7 unstained tumor slides) was collected for retrospective central laboratory testing. HER-2 DNA amplification was determined by FISH, and protein levels by IHC. qRT-PCR for HER-2 was performed on extracted RNA; baseline HER-2 ECD ELISA was performed on pt sera. HER-2 data for each pt were compared with pt's best response. Results: As of August 29, 2008, 112 pts had enrolled; 107 were efficacy-evaluable pts with median 4.4 mos follow-up. There were 42/107 (39.3%) partial responses (PR) (investigator assessment). Of 86 pts centrally tested, 64 (74.4%) were confirmed HER-2+ (FISH+ and/or IHC 3+), with 32/64 (50%) PR. Of 76 pts tested by both FISH and IHC, 15/76 (19.7%) were confirmed HER-2- (FISH- and IHC 2+/1/0), with 2/15 (13.3%) PR. In HER-2+ pts, response rates did not correlate with high versus low FISH+ counts, nor with HER-2 ECD levels. Among 39 HER-2+ (FISH+ and/or IHC3+) efficacy-evaluable pts with qRT-PCR data, there were 13/19 (68.4%) PR for pts with qRT-PCR above median levels, and 7/20 (35.0%) PR for pts with qRT-PCR below median. Conclusions: HER-2+ pts (by central retesting) had better responses to T-DM1 than HER-2- pts, although a small number of PR were observed in HER-2- pts. Assessment of HER-2 expression by qRT-PCR may identify pts more likely to respond to T-DM1 therapy. Updated data, including additional diagnostic markers, will be presented at the meeting.

[Table: see text]

Clinical pharmacokinetics of erlotinib (E) in glioblastoma multiforme (GBM) patients and its implication for dosing

2010

Background: E is an orally active, highly potent and selective inhibitor of the epidermal growth factor receptor (EGFR). Preliminary results from both Phase I and Phase II trials of E in GBM patients have been reported (ASCO 2003, Abs#394 and ASCO 2004, Abs#1555). The purpose of this analysis is to characterize E PK in this patient population when administered with or without CYP3A4 enzyme inducing anti-epileptic drugs (EIAEDs) and to identify a dose to provide equivalent exposure during concomitant therapy in GBM patients. Methods: Intensive PK data were collected in the Phase I study and plasma trough concentration data were collected in the Phase II study at steady-state. A total of 775 E concentrations from 107 patients were available for the analysis. A population PK approach (NONMEM) was used to characterize the clinical PK in this patient population and the effect of EIAEDs on the PK of E. Results: Co-administration of EIAEDs was shown to increase the E clearance (CL/F) by 230% in GBM patients. This effect is similar to that seen in a previous drug-drug interaction study with a CYP3A4 enzyme inducer (rifampicin) in healthy volunteers. For patients with no EIAEDs, population estimates and the %CV of inter-individual variance for CL/F and Vc/F of erlotinib were 5.63 L/hr (44%) and 388 L (40%), respectively. Conclusions: Based on the modeling results, for GBM patients with EIAEDs, an estimate of erlotinib dose of 500 mg/d is needed to achieve an equivalent exposure as patients who receive the dose of 150 mg/d with no EIAEDs. The new population PK model provides an operational tool to predict E exposure during treatment, and simulate alternative dosing regimens for GBM patients.

[Table: see text]

Azacitidine Induces Demethylation of the Epstein-Barr Virus Genome in Tumors

Purpose

To determine whether therapy with a DNA methyltransferase inhibitor is effective in achieving demethylation and gene re-expression in tumor DNA in patients.

Methods

Biopsy specimens were obtained from patients with Epstein-Barr virus-associated tumors, enrolled on a clinical trial of 5-azacitidine, within 72 hours of the conclusion of the last infusion of the first cycle of therapy, and compared to pretreatment specimens. Methylation-specific polymerase chain reaction, bisulfite genomic sequencing, and immunohistochemistry were used to assess demethylation and gene re-expression.

Results

Substantial degrees of demethylation were detected in all latent and lytic Epstein-Barr virus promoters examined. Immunohistochemistry suggested activation of a previously silent viral antigen expression in one instance.

Conclusion

Pharmacologic reversal of dense CpG methylation in tumor tissue can be achieved in patients.

High-dose 131I-metaiodobenzylguanidine therapy for 12 patients with malignant pheochromocytoma

BACKGROUND

131I-Metaiodobenzylguanidine (131I-MIBG) can be used systemically to treat malignant pheochromocytoma. To improve outcome, the authors used higher levels of activity of 131I-MIBG than previously reported. The authors reported the response rates and toxicity levels in patients with malignant pheochromocytoma or paraganglioma who were treated with high-dose 131I-MIBG.

METHODS

Following debulking surgery and stem cell harvest, 12 patients with malignant pheochromocytoma or paraganglioma were treated with 131I-MIBG. Five had received previous external beam radiation and/or chemotherapy. The median single treatment dose was 800 mCi (37 gigabecquerels; range, 386-866 mCi) or 11.5 mCi/kg (range, 5.6-18.3 mCi/kg). The median cumulative dose was 1015 mCi (range, 386-1690 mCi).

RESULTS

Three patients had a complete response, two of whom had soft tissue and skeletal metastases. Their median follow-up was 45 months (range, 23-101 months). Seven patients had a partial response (PR), with a median follow-up 43 months (range, 6-47 months). Two patients without a response died with progressive disease (PD) and 2 patients with an initial PR died of PD at 13 and 11 months, respectively. Grade 3 thrombocytopenia occurred after 79% (15 of 19) of treatments had been administered. Grade 3 and 4 neutropenia followed 53% (10 of 19) and 19% (4 of 19) of treatments, respectively. One patient required stem cell infusion, and one developed primary ovarian failure.

CONCLUSIONS

The single and cumulative doses of 131I-MIBG were approximately 2-3.5 times higher than those used at other centers. Unlike previous reports, two patients with both skeletal and soft tissue metastases had a complete response. Hematologic toxicity was significant but tolerable. High-dose 131I-MIBG may lead to long-term survival in patients with malignant pheochromocytoma.

Encapsulated plasmid DNA treatment for human papillomavirus 16-associated anal dysplasia: a Phase I study of ZYC101

High-grade dysplasia induced by high-risk types of human papillomavirus (HPV) precedes invasive cancer in anal squamous epithelium just as it does in the cervix. A therapeutic HPV vaccine strategy as a potential treatment for anal dysplasia was tested in a standard Phase I dose escalation trial. The primary objective was to evaluate the safety of the agent; additional study aims were to evaluate the histological response, immune response, and effect on anal HPV-16 infection. Each subject was treated with four i.m. injections of 50-400 microg of ZYC101 at 3-week intervals. ZYC101 is composed of plasmid DNA encapsulated in biodegradable polymer microparticles. The plasmid DNA encodes for multiple HLA-A2-restricted epitopes derived from the HPV-16 E7 protein, one of two HPV oncoproteins consistently expressed in neoplastic cells. Fifty-six potential anal dysplasia subjects were screened to identify 12 eligible subjects with HPV-16 anal infection and a HLA-A2 haplotype. The investigational agent was well tolerated in all subjects at all dose levels tested. Three subjects experienced partial histological responses, including one of three subjects receiving the 200-microg dose and two subjects at the 400-microg dose level. Using a direct Elispot, 10 of 12 subjects demonstrated increased immune response to the peptide epitopes encoded within ZYC101; each continued to show elevated immune responses 6 months after the initiation of therapy. These results support the continued investigation of a therapeutic vaccination strategy for anal dysplasia.

Oral eniluracil/5-fluorouracil in patients with inoperable hepatocellular carcinoma

BACKGROUND

Conventional systemic chemotherapy currently available for patients with inoperable hepatocellular carcinoma is ineffective. The purpose of this study was to evaluate the safety and efficacy of eniluracil/5-fluorouracil (5-FU) in the treatment of patients with this highly refractory disease.

PATIENTS AND METHODS

This multicenter, open-label study evaluated a 28-day oral regimen of 5-FU (1 mg/m2 twice daily) plus the dihydropyrimidine dehydrogenase inhibitor, eniluracil (10 mg/m2 twice daily), in patients with chemotherapy-naive or anthracycline-refractory inoperable hepatocellular carcinoma.

RESULTS

A total of 36 patients enrolled into the study. No patient showed a confirmed partial or complete tumor response, although nine patients (25%) had a best response of stable disease. The median duration of progression-free survival was 9.6 weeks [95% confidence interval (CI) 9.1-10.6 weeks], and the median duration of overall survival was 32.7 weeks (95% CI 17.4-71.6 weeks). Eniluracil/5-FU was well tolerated. Diarrhea, the most frequent treatment-related non-hematological toxicity, occurred in 11 patients (31%). Hematological toxicities were infrequent and usually mild.

CONCLUSIONS

Eniluracil/5-FU as a 28-day oral outpatient regimen is well tolerated by patients with inoperable hepatocellular carcinoma, although minimal activity was observed when given as monotherapy at the dose used in this study.

The restricted cellular host range of human herpesvirus 8

DESIGN

A selection of primary and transformed cell types were evaluated for their susceptibility to infection with human herpesvirus 8 (HHV-8)/Kaposi's sarcoma-associated herpesvirus.

METHODS

Sources of HHV-8 included Kaposi's sarcoma lesion punch biopsies that were either cocultured directly with target cells or that were first cocultured with human lymphocytes to derive HHV-8-containing fluids that were inoculated onto target cells. HHV-8 was also obtained from primary effusion lymphoma-derived cell lines. Techniques to detect infection included the PCR, immunofluorescence assays and in situ hybridization.

RESULTS

Susceptible cells included human umbilical cord blood mononuclear cells (UCMC), adult CD19 B cells, macrophages and certain endothelial cells of human and animal origin, including some that are transformed with human papilloma virus type 16 E6 and E7 genes. The infection of lymphocytes did not yield established lymphoblastoid cell lines (LCL) and virus infection persisted for only 4-7 days. However, long-term HHV-8 infection of UCMC could be achieved by coinfection with Epstein-Barr virus. HHV-8 could also infect UCMC LCL recently derived by Epstein-Barr virus transformation, but long-established LCL could not be infected with HHV-8.

CONCLUSIONS

These data provide further biological evidence in cell culture for the limited cellular host range of HHV-8 to CD19 B cells, macrophages, and certain endothelial cells.

The significance of pretreatment CD4 count on the outcome and treatment tolerance of HIV-positive patients with anal cancer

PURPOSE

To assess the outcome and tolerance of HIV-positive patients with anal cancer to standard therapy based on their pretreatment CD4 count.

METHODS AND MATERIALS

Between 1991 and 1997, 17 HIV-positive patients with anal cancer and documented pretreatment CD4 counts were treated at the University of California, San Francisco or its affiliated hospitals with either concurrent chemotherapy and radiation or radiation alone. The outcome and complications of treatment were correlated with the patients' pretreatment CD4 count.

RESULTS

Disease for all 9 patients with pretreatment CD4 counts > or = 200 was controlled with chemoradiation. Although four required a treatment break of 2 weeks because of toxicity, none required hospitalization. Of the 8 patients with pretreatment CD4 counts < 200, 4 experienced decreased counts, intractable diarrhea, or moist desquamation requiring hospitalization. Additionally, 4 of these 8 ultimately required a colostomy either for a therapy-related complication or for salvage. Nevertheless, 6/7 in this group who received concurrent chemotherapy and radiation had their disease controlled, whereas the patient treated with radiation alone failed and required a colostomy for salvage.

CONCLUSION

Patients with CD4 > or = 200 had excellent disease control with acceptable morbidity. Patients with CD4 < 200 had markedly increased morbidity; however, disease was ultimately controlled in 7/8 patients.

Advances and future challenges in non-Hodgkin's lymphoma

The mortality and morbidity burden of Non-Hodgkin's lymphoma (NHL) is increasing within the human immunodeficiency virus- (HIV-) infected population. Recent improvements in HIV management has meant overall reductions in deaths, especially those due to opportunistic infections, and while the outcome of HIV-related NHL may now be somewhat less grim, the incidence remains high and outcome poor. The median survival of those with HIV-related NHL is only approximately 7 months, although those with high CD4 lymphocyte counts seem to do somewhat better. Improved management of the underlying HIV infection, more effective infusional chemotherapy regimens, moderately effective second line regimens, and new investigational approaches all offer promising hope that improvements will soon be seen for the treatment of HIV-related systemic NHL. Immunotherapy, monoclonal antibodies, and adoptive immunotherapy targeting Epstein Barr virus (EBV) all represent novel experimental treatment approaches that are becoming possible based on our increased understanding of the pathogenesis of HIV-related lymphoma. Primary central nervous system lymphoma (PCNSL) in HIV patients has declined in incidence and there now is a rapid, less invasive diagnostic test. The presence of EBV DNA in the cerebral spinal fluid of HIV patients with focal brain lesions strongly suggests a diagnosis of PCNSL. Unfortunately, this disease remains difficult to treat in such an immunocompromised patient population. Further work is needed in order to prevent and effectively manage these diseases.

Intra-abdominal desmoplastic small round-cell tumor: expansion of the pathologic profile

This report describes an intra-abdominal desmoplastic small round-cell tumor in a 29-year-old man that significantly differed from the classically described appearances of this unique tumor. It showed extensive papillary areas, no necrosis, and very little desmoplasia. The latter was limited, paucicellular, and present in areas separate from the papillary structures. Also, areas of back-to-back, single-cell infiltration, which mimicked lobular breast carcinoma, were present. These epithelial features suggested the diagnosis of adenocarcinoma or peculiar mesothelioma. But, the immunohistochemical features (tumor cells positive for keratin, desmin, and vimentin) were more consistent with an intra-abdominal desmoplastic small round-cell tumor. The diagnosis became clear after application of reverse transcriptase-polymerase chain reaction techniques to formalin-fixed, paraffin-embedded tissue, which showed the presence of a 100-base pair product containing the fusion junction of Ewing's sarcoma-1 exon 7 to Wilms' tumor-1 exon 8. This feature is considered unique to intra-abdominal desmoplastic small round-cell tumors. This case illustrates the less common histologic findings that can be found in intra-abdominal desmoplastic small round-cell tumor. This deviation from the classic histologic findings may be an expression of an uncommon morphologic variant and/or partially produced by the effects of prior chemotherapy. In either event, only by illustrating the various histologic appearances of intra-abdominal desmoplastic small round-cell tumor are the chances increased for the accurate diagnosis of this aggressive neoplasm with a poor prognosis.