Efficacy and safety of mogamulizumab by patient baseline blood tumour burden: a post hoc analysis of the MAVORIC trial.

BACKGROUND: Mogamulizumab was compared with vorinostat in the phase 3 MAVORIC trial (NCT01728805) in 372 patients with relapsed/refractory mycosis fungoides (MF) or Sézary syndrome (SS) who had failed ≥1 prior systemic therapy. Mogamulizumab significantly prolonged progression-free survival (PFS), with a superior objective response rate (ORR) vs. vorinostat. OBJECTIVES: This post hoc analysis was performed to evaluate the effect of baseline blood tumour burden on patient response to mogamulizumab. METHODS: PFS, ORR, time to next treatment (TTNT), skin response (modified Severity-Weighted Assessment Tool [mSWAT]) and safety were assessed in patients stratified by blood classification (B0 [n = 126], B1 [n = 62], or B2 [n = 184], indicating increasing blood involvement). RESULTS: Investigator-assessed PFS was longer for mogamulizumab versus vorinostat across all blood classes, significantly so for B1 and B2 patients. ORR was higher with mogamulizumab than with vorinostat in all blood classification groups and more markedly so with escalating B class (B0: 15.6% vs. 6.5%, P = 0.0549; B1: 25.8% vs. 6.5%, P = 0.2758; B2: 37.4% vs. 3.2%, P < 0.0001). TTNT was significantly longer for patients treated with mogamulizumab versus vorinostat with B1 (12.63 vs. 3.07 months; HR 0.32 [95% CI 0.16-0.67]; P = 0.0018) and B2 (13.07 vs. 3.53 months; HR 0.30 [95% CI 0.21-0.43]; P < 0.0001) blood involvement. In the mogamulizumab arm, 81 patients (43.5%) had ≥50% change in the mSWAT vs. 41 patients (22.0%) with vorinostat; mSWAT improvements with mogamulizumab occurred most often in B1 and B2 patients. Rapid, sustained reductions were seen in CD4+ CD26- cell counts and CD4:CD8 ratios in mogamulizumab patients for all B classes. Treatment-emergent adverse events were less frequent overall with mogamulizumab and similar in frequency regardless of B class. CONCLUSIONS: This post hoc analysis indicates greater clinical benefit with mogamulizumab vs. vorinostat in patients with MF and SS classified as having B1 and B2 blood involvement.

Utility of ¹8fluoro-deoxyglucose positron emission tomography for prognosis and response assessments in a phase 2 study of romidepsin in patients with relapsed or refractory peripheral T-cell lymphoma.

BACKGROUND: For patients with peripheral T-cell lymphoma (PTCL), the value of (18)fluoro-deoxyglucose positron emission tomography (FDG-PET) scans for assessing prognosis and response to treatment remains unclear. The utility of FDG-PET, in addition to conventional radiology, was examined as a planned exploratory end point in the pivotal phase 2 trial of romidepsin for the treatment of relapsed/refractory PTCL. PATIENTS AND METHODS: Patients received romidepsin at a dose of 14 mg/m(2) on days 1, 8, and 15 of 28-day cycles. The primary end point was the rate of confirmed/unconfirmed complete response (CR/CRu) as assessed by International Workshop Criteria (IWC) using conventional radiology. For the exploratory PET end point, patients with at least baseline FDG-PET scans were assessed by IWC + PET criteria. RESULTS: Of 130 patients, 110 had baseline FDG-PET scans, and 105 were PET positive at baseline. The use of IWC + PET criteria increased the objective response rate to 30% compared with 26% by conventional radiology. Durations of response were well differentiated by both conventional radiology response criteria [CR/CRu versus partial response (PR), P = 0.0001] and PET status (negative versus positive, P < 0.0001). Patients who achieved CR/CRu had prolonged progression-free survival (PFS, median 25.9 months) compared with other response groups (P = 0.0007). Patients who achieved PR or stable disease (SD) had similar PFS (median 7.2 and 6.3 months, respectively, P = 0.6427). When grouping PR and SD patients by PET status, patients with PET-negative versus PET-positive disease had a median PFS of 18.2 versus 7.1 months (P = 0.0923). CONCLUSIONS: Routine use of FDG-PET does not obviate conventional staging, but may aid in determining prognosis and refine response assessments for patients with PTCL, particularly for those who do not achieve CR/CRu by conventional staging. The optimal way to incorporate FDG-PET scans for patients with PTCL remains to be determined. TRIAL REGISTRATION: NCT00426764.

Demonstration of event position reconstruction based on diffusion in the NEXT-white detector.

Noble element time projection chambers are a leading technology for rare event detection in physics, such as for dark matter and neutrinoless double beta decay searches. Time projection chambers typically assign event position in the drift direction using the relative timing of prompt scintillation and delayed charge collection signals, allowing for reconstruction of an absolute position in the drift direction. In this paper, alternate methods for assigning event drift distance via quantification of electron diffusion in a pure high pressure xenon gas time projection chamber are explored. Data from the NEXT-White detector demonstrate the ability to achieve good position assignment accuracy for both high- and low-energy events. Using point-like energy deposits from 83mKr calibration electron captures (E∼45 keV), the position of origin of low-energy events is determined to 2 cm precision with bias <1mm. A convolutional neural network approach is then used to quantify diffusion for longer tracks (E≥1.5 MeV), from radiogenic electrons, yielding a precision of 3 cm on the event barycenter. The precision achieved with these methods indicates the feasibility energy calibrations of better than 1% FWHM at Qßß in pure xenon, as well as the potential for event fiducialization in large future detectors using an alternate method that does not rely on primary scintillation.

Barium Chemosensors with Dry-Phase Fluorescence for Neutrinoless Double Beta Decay.

The nature of the neutrino is one of the major open questions in experimental nuclear and particle physics. The most sensitive known method to establish the Majorana nature of the neutrino is detection of the ultra-rare process of neutrinoless double beta decay. However, identification of one or a handful of decay events within a large mass of candidate isotope, without obfuscation by backgrounds is a formidable experimental challenge. One hypothetical method for achieving ultra- low-background neutrinoless double beta decay sensitivity is the detection of single 136Ba ions produced in the decay of 136Xe ("barium tagging"). To implement such a method, a single-ion-sensitive barium detector must be developed and demonstrated in bulk liquid or dry gaseous xenon. This paper reports on the development of two families of dry-phase barium chemosensor molecules for use in high pressure xenon gas detectors, synthesized specifically for this purpose. One particularly promising candidate, an anthracene substituted aza-18-crown-6 ether, is shown to respond in the dry phase with almost no intrinsic background from the unchelated state, and to be amenable to barium sensing through fluorescence microscopy. This interdisciplinary advance, paired with earlier work demonstrating sensitivity to single barium ions in solution, opens a new path toward single ion detection in high pressure xenon gas.

Signaling from protease-activated receptor-1 inhibits migration and invasion of breast cancer cells.

Proteases give cancer a defining characteristic of being able to break through extracellular matrix barriers and invade into other tissues in response to chemotactic signals. Recently, the cell surface protease-activated receptor (PAR)-1 has been shown to act as a chemokine receptor in inflammatory cells, and its expression is tightly correlated with metastatic propensity of breast cancer cells. The aim of the present study was to determine whether activation of PAR1 or the other known PARs (PAR2-4) can regulate migration and invasion of breast cancer cells. We found that the highly invasive MDAMB231 breast cancer cell line expressed very high levels of functional PAR1, PAR2, and PAR4, whereas minimally invasive MCF7 cells had trace amounts of PAR1 and low levels of PAR2 and PAR4. Despite the differences in expression, PAR2 and PAR4 acted as chemokine receptors in both invasive and minimally invasive breast cell lines. Quite unexpectedly, we found that activation of PAR1 with thrombin or the peptide agonist SFLLRN markedly inhibited invasion and migration of MDAMB231 cells when applied as a concentration gradient in the direction of cell movement. Additionally, we demonstrated that inhibition of chemotaxis was mediated through a G(i)/phosphoinositide-3-OH kinase-dependent pathway. Activation of G(i) signaling with epinephrine or wasp venom mastoparan also inhibited invasion and migration of the breast cancer cells. These findings suggest that therapeutics targeted toward G(i)-couplers that are selectively expressed in breast cancer cells could prove beneficial in halting the progression of invasive breast cancer.

The use of basiliximab-infliximab combination for the treatment of severe gastrointestinal acute GvHD.

After allogeneic stem cell transplant, severe grade III-IV gastrointestinal (GI) acute GvHD is associated with significant morbidity and mortality, and generally results in poor outcomes. Salvage therapy for patients who fail steroid therapy is not well defined in the literature. In the current retrospective study, we reviewed our experience with the combination of basiliximab and infliximab in 21 patients with severe, grade III-IV GI acute GvHD of whom 16 met the definition for steroid-refractory disease. The overall response rate was 76%, with 43% CR at a median time of 21 days after beginning treatment. The survival at 1 year was 24%, with most deaths due to complications from GvHD and recurrence of primary disease. All five of the long-term survivors have chronic GvHD. On the basis of a review of the literature, this regimen does not seem to be significantly more effective than other strategies for severe GI GvHD and seems to be worse than the results reported for basiliximab alone. Future studies of single-agent basiliximab and newer agents are required.

EphrinB2 repression through ZEB2 mediates tumour invasion and anti-angiogenic resistance.

Diffuse invasion of the surrounding brain parenchyma is a major obstacle in the treatment of gliomas with various therapeutics, including anti-angiogenic agents. Here we identify the epi-/genetic and microenvironmental downregulation of ephrinB2 as a crucial step that promotes tumour invasion by abrogation of repulsive signals. We demonstrate that ephrinB2 is downregulated in human gliomas as a consequence of promoter hypermethylation and gene deletion. Consistently, genetic deletion of ephrinB2 in a murine high-grade glioma model increases invasion. Importantly, ephrinB2 gene silencing is complemented by a hypoxia-induced transcriptional repression. Mechanistically, hypoxia-inducible factor (HIF)-1α induces the EMT repressor ZEB2, which directly downregulates ephrinB2 through promoter binding to enhance tumour invasiveness. This mechanism is activated following anti-angiogenic treatment of gliomas and is efficiently blocked by disrupting ZEB2 activity. Taken together, our results identify ZEB2 as an attractive therapeutic target to inhibit tumour invasion and counteract tumour resistance mechanisms induced by anti-angiogenic treatment strategies.

Rearrangement and altered expression of the NFKB-2 gene in human cutaneous T-lymphoma cells.

The NF-kappa b/Rel and I kappa B proteins are important regulators of lymphocyte activation and gene expression. We have identified a rearrangement of the NFKB-2 gene in the HUT 78 human cutaneous T-cell leukemia (CTCL) line, cDNA and genomic DNA sequence predicted the presence of a truncated 80 kD NFKB-2 precursor protein (p80HT), instead of the normal p100 protein. No wild-type allele was identified. Elevated levels of two aberrantly sized RNAs were detected, and high levels of p80HT and processed p52 protein were present in HUT 78 cell nuclei. The p52 protein bound to a palindromic kappa B DNA motif, however p80HT did not. Rearrangement of the NFKB-2 gene was also detected in DNA from two patients with CTCL. Rearrangement and overexpression of the NFKB-2 gene may contribute to the genesis of a subset of T-cell malignancies.

Neurotoxicity of purine analogs: a review.

PURPOSE: The purine analogs, fludarabine, cladribine, and pentostatin, are active against a broad spectrum of indolent lymphoid malignancies. They also have similar toxicities, including myelosuppression, immunosuppression, and sporadic neurotoxicity. This review compares the spectrum of neurotoxicity of each of these agents. Now that these drugs are commercially available and are being widely used, physicians should be aware of potentially serious side effects that may be encountered. METHODS: The literature was searched using MedLine and Cancerline, as well as the bibliographies of published reports through the fall of 1993. In addition, case records from National Cancer Institute (NCI) Group C protocols were reviewed for fludarabine in chronic lymphocytic leukemia (CLL), and cladribine and pentostatin in hairy cell leukemia (HCL), as well as adverse drug reactions reported to the NCI from January 1980 through September 1993. RESULTS: At higher than recommended doses, life-threatening and fatal neurotoxicity were encountered with all three drugs. At the recommended doses, each agent induced neurotoxicity in approximately 15% of patients, mostly mild and reversible. However, severe neurologic complications were reported; these were occasionally delayed, sometimes fatal, but often at least partially reversible. CONCLUSION: The doses of these three agents should not be increased above the recommended levels. Development of moderate or worse neurotoxicity should result in discontinuation of that drug.

Costimulation of cutaneous T-cell lymphoma cells by interleukin-7 and interleukin-2: potential autocrine or paracrine effectors in the Sézary syndrome.

PURPOSE: To examine interleukin-7 (IL7)- and interleukin-2 (IL2)-induced proliferation of Sézary lymphoma cells and to consider if an autocrine or paracrine growth-stimulatory circuit involving IL7 exists in the Sézary syndrome (SS). MATERIALS AND METHODS: Fresh Sézary lymphoma cells were maintained in short-term culture in the presence of cytokines, and growth was measured by incorporation of (3H)-thymidine (TdR). Expression of IL7 and IL7 and IL2 receptors (IL7-R and IL2-R, respectively) was assessed by polymerase chain amplification of first-strand complementary DNA (RT-PCR), by affinity cross-linking of radioactive iodine-125-IL7, and by dual-color fluorescence-activated cell analysis. IL-7 production was measured by immunoassay. RESULTS: Sézary lymphoma cells from seven patients showed synergistic (five of seven) or additive (two of seven) proliferation when cultured in the presence of IL2 and IL7, as compared with culture with either cytokine alone. Two patients with evidence of synergistic stimulation of [3H]-TdR incorporation showed IL7-R gene expression by RT-PCR and IL7 affinity cross-linking. Incubation of all seven patients' cells with IL7 induced coexpression to varying degrees of IL7-R and IL2-R. Sézary lymphoma cells from at least three of five patients studied expressed IL7 mRNA, and skin from three of five patients studied, as well as normal skin, expressed IL7 mRNA by RT-PCR. CONCLUSION: Sézary lymphoma cells respond by proliferation to IL7 plus IL2, and in some instances produce IL7. Therapeutic maneuvers should be pursued to take advantage of this potential autocrine or paracrine growth-stimulatory mechanism.

Phase II study of pentostatin and intermittent high-dose recombinant interferon alfa-2a in advanced mycosis fungoides/Sézary syndrome.

PURPOSE: This phase II study was undertaken to assess the efficacy and toxicity of alternating administration of pentostatin (deoxycoformycin [DCF]) and interferon alfa-2a (IFN) in patients with advanced or refractory mycosis fungoides (MF) or the Sézary syndrome (SS). PATIENTS AND METHODS: Forty-one patients underwent therapy with alternating cycles of DCF 4 mg/m2 intravenously (IV) days 1 through 3 and IFN 10 million U/m2 intramuscularly (IM) day 22, and 50 million U/m2 intramuscularly (IM) days 23 through 26. Twenty-nine patients had not responded to prior chemotherapy or total-skin electron-beam irradiation (TSEB), six had not responded to topical therapies, and six had no previous treatment. RESULTS: Two patients achieved a complete response (CR) and 15 achieved a partial response (PR), for an overall response rate of 41% (95% confidence interval, 26% to 58%). No responses were observed in the seven patients with visceral involvement. The median progression-free survival of patients who responded was 13.1 months. IFN-related constitutional symptoms were reported in 39% of patients; severe toxicities included cardiomyopathy in one patient, acute and chronic pulmonary dysfunction in four, and reversible mental status changes in two. Seven patients developed herpes zoster during therapy and six had staphylococcal bacteremia. CONCLUSION: These results suggest that the combination of DCF and IFN is an active regimen in MF patients without visceral involvement.

Phase II trial of fludarabine phosphate and interferon alfa-2a in advanced mycosis fungoides/Sézary syndrome.

PURPOSE: This phase II study was undertaken to assess the efficacy and toxicity of the addition of continuous low-dose interferon alfa-2a (IFN) to fludarabine in patients with advanced or refractory mycosis fungoides (MF) or the Sézary syndrome (SS). PATIENTS AND METHODS: Thirty-five patients were treated with fludarabine 25 mg/m2 intravenously (IV) on days 1 to 5 every 28 days along with IFN 5 x 10(6) U/m2 subcutaneously three times per week continuously for up to eight cycles. IFN doses were escalated to 7.5 x 10(6)/m2 at day 29 if constitutional toxicities were less than grade 3. Twenty-one patients had not responded to prior chemotherapy or total-skin electron-beam irradiation (TSEB), and 10 of these had received prior deoxycoformycin (pentostatin; DCF) and intermittent high-dose IFN; seven had received only topical therapies, and seven were untreated. RESULTS: Four patients achieved a complete response (CR) and 14 achieved a partial response (PR) for an overall response rate of 51% (95% confidence interval, 35% to 70%). Four of 11 patients with visceral involvement responded. The median progression-free survival duration of the patients who responded was 5.9 months, and three of the complete responders are in unmaintained response after 18 to 35 months. Grade 3 or 4 hematologic toxicity occurred in 21 patients, including two who developed persistent bone marrow aplasia. Eighteen patients developed infections during therapy, including five with herpes zoster, one with Pneumocystis carinii, one with extrapulmonary tuberculosis, and two with disseminated toxoplasmosis. CONCLUSION: The combination of fludarabine with continuous low-dose IFN is an active regimen in patients with advanced MF/SS, including patients with visceral involvement and patients who progressed after prior therapy with DCF and IFN. This regimen has induced unmaintained remissions in a small subset of patients.

Pivotal phase III trial of two dose levels of denileukin diftitox for the treatment of cutaneous T-cell lymphoma.

PURPOSE: The objective of this phase III study was to determine the efficacy, safety, and pharmacokinetics of denileukin diftitox (DAB389IL-2, Ontak [Ligand Pharmaceuticals Inc, San Diego, CA]) in patients with stage Ib to IVa cutaneous T-cell lymphoma (CTCL) who have previously received other therapeutic interventions. PATIENTS AND METHODS: Patients with biopsy-proven CTCL that expressed CD25 on > or = 20% of lymphocytes were assigned to one of two dose levels (9 or 18 microg/kg/d) of denileukin diftitox administered 5 consecutive days every 3 weeks for up to 8 cycles. Patients were monitored for toxicity and clinical efficacy, the latter assessed by changes in disease burden and quality of life measurements. Antibody levels of antidenileukin diftitox and anti-interleukin-2 and serum concentrations of denileukin diftitox were also measured. RESULTS: Overall, 30% of the 71 patients with CTCL treated with denileukin diftitox had an objective response (20% partial response; 10% complete response). The response rate and duration of response based on the time of the first dose of study drug for all responders (median of 6.9 months with a range of 2.7 to more than 46.1 months) were not statistically different between the two doses. Adverse events consisted of flu-like symptoms (fever/chills, nausea/vomiting, and myalgias/arthralgias), acute infusion-related events (hypotension, dyspnea, chest pain, and back pain), and a vascular leak syndrome (hypotension, hypoalbuminemia, edema). In addition, 61% of the patients experienced transient elevations of hepatic transaminase levels with 17% grade 3 or 4. Hypoalbuminemia occurred in 79%, including 15% with grade 3 or 4 changes. Tolerability at 9 and 18 microg/kg/d was similar, and there was no evidence of cumulative toxicity. CONCLUSION: Denileukin diftitox has been shown to be a useful and important agent in the treatment of patients whose CTCL is persistent or recurrent despite other therapeutic interventions.

Prospective study of extracorporeal photopheresis in steroid-refractory or steroid-resistant extensive chronic graft-versus-host disease: analysis of response and survival incorporating prognostic factors.

We enrolled 25 patients with extensive, steroid-refractory chronic graft-versus-host disease (cGVHD) in a prospective trial evaluating the efficacy of extracorporeal photophoresis (ECP) in both skin and visceral cGVHD. The median time from transplant to initiation of ECP was 790 days. ECP was administered for 2 consecutive days every 2 weeks in 17 patients and once a week in eight patients until best response or stable disease. The median duration of therapy was 9 months (range 3-24 months). In all, 20 patients had improvement in cutaneous GVHD and six had healing of oral ulcerations. Steroid sparing or discontinuation of immunosuppressive medications was possible in 80% of patients. Response rates were similar between patients receiving treatment weekly vs every 2 weeks and in patients commencing ECP less than vs greater than 18 months from transplant (70 vs 66%). When patients were stratified based on the Akpek prognostic score, there was no difference in overall response between the favorable (Akpek score<2.5) and unfavorable risk groups, but patients with progressive onset cGVHD tended to have a higher response than those with de novo onset. In summary, we report improvement in skin and/or visceral cGVHD in 71% overall and 61% of high-risk patients.

Arginine butyrate downregulates p210 bcr-abl expression and induces apoptosis in chronic myelogenous leukemia cells.

Downregulation of bcr-abl expression in the chronic myelogenous leukemia cell line K562 using antisense oligonucleotides has been shown to enhance the sensitivity of the cells to apoptotic stimuli, suggesting that p210 bcr-abl, like bcl-2 functions as an anti-apoptosis factor (McGahon A et al, Blood 1994, 83: 1179). In these experiments, the inhibition of p210 bcr-abl expression alone was not sufficient to induce apoptosis. We demonstrated that exposure to low doses (0.5 mM) of a butyric acid analog, arginine butyrate, was capable of inducing apoptosis in selected leukemia cell lines, including K562 cells, and in fresh leukemia cells from patients with chronic myelogenous leukemia. To further explore the mechanisms of this effect, we examined expression of p210 bcr-abl after butyrate exposure and found a dose-related inhibition of p210 bcr-abl protein without concordant change in other phosphoproteins, including the JAK-1 kinase. Further analysis revealed that the inhibition of bcr-abl expression occurs due to transcriptional regulation of the bcr-abl gene by arginine butyrate. These results suggest that arginine butyrate and other butyrate analogs alone or in combination may be useful in the therapy of patients with chronic myelogenous leukemia or bcr-abl expressing acute leukemias.

Phase I study of the pharmacokinetics of a radioimmunoconjugate, 90Y-T101, in patients with CD5-expressing leukemia and lymphoma.

Ten patients with advanced or refractory CD5-expressing hematologic neoplasms [two with chronic lymphocytic leukemia and eight with cutaneous T-cell lymphoma (CTCL)] were treated in a Phase I study with the radioimmunoconjugate 90Y-T101, which targets CD5+ lymphocytes. Prior imaging studies using 111In-T101 demonstrated uptake in involved lymph nodes and skin in patients with CTCL, and Phase I studies with unmodified T101 demonstrated transient responses. In this study, patients were treated with 5 or 10 mCi of 90Y chelated to T101 via isothiocyanatobenzyl diethylenetriamine pentaacetic acid, along with tracer doses of 111In-T101 for imaging. The biodistribution of the radioimmunoconjugate was determined by measuring 90Y and 111In blood clearance, urine excretion, and accumulation in bone marrow and in involved skin lesions. The intravascular pharmacokinetics of 90Y were predicted by 111In-labeled T101. The greatest differences in biodistribution between 111In and 90Y were in the higher bone accumulation of 90Y and its lower urinary excretion. Imaging studies demonstrated targeting of skin lesions and involved lymph nodes in CTCL patients. The predominant toxicity was bone marrow suppression. Rapid antigenic modulation of CD5 on circulating T and B cells was observed. Recovery of T-cell populations occurred within 2-3 weeks; however, suppression of B-cell populations persisted after 5+ weeks. All CTCL patients developed human antimouse antibody after one cycle and thus were not retreated; one patient with chronic lymphocytic leukemia received a second cycle of therapy. Partial responses occurred in five patients, two with chronic lymphocytic leukemia and three with CTCL. The median response duration was 23 weeks. One CTCL patient who subsequently received electron beam irradiation to a residual lesion is disease-free after 6 years.

Interleukin-2 fusion protein: an investigational therapy for interleukin-2 receptor expressing malignancies.

DAB389IL-2 is an interleukin-2 receptor (IL-2R) specific fusion protein with a molecular weight of 58 kD containing the enzymatic and translocation domains of diphtheria toxin (DT) and human IL-2. This fusion protein is able to direct the cytocidal action of the DT enzymatic region only to cells which bear the IL-2R. The human IL-2R exists in three forms: low, intermediate and high affinity. The high-affinity form is believed to be the biologically relevant form on mature, activated T-lymphocytes, B-lymphocytes and monocytes. DAB389IL-2 is able to bind selectively to the high-affinity IL-2R in a concentration-dependent manner, and once bound is internalised via receptor-mediated endocytosis. Upon acidification of the formed vesicle, the enzymatic portion of the fusion protein is believed to pass into the cytosol where it ultimately inhibits protein synthesis by inactivation of elongation factor-2, resulting in cell death. The constitutive expression of the IL-2R on certain leukaemic and lymphomatous cells of T and B cell origin has been reported to occur in patients with chronic lymphocytic leukaemia, cutaneous T cell lymphoma (CTCL), Hodgkin's disease and non-Hodgkin's lymphomas (NHLs). A multicentre DAB389IL-2 dose-escalation study of patients with IL-2R expressing lymphomas has been conducted. A 10-fold range of doses were evaluated on a five-daily dose schedule. Patients received up to six courses, with an additional two courses permitted for patients with partial responses that appeared to be still improving after six courses. Most adverse experiences were transient and mild. Preliminary assessment of response indicated five complete responses (CR, duration ongoing at 20, 11, 7, 5 and 4 months) and seven partial responses (PR, duration 3-20 months) in the 35 patients with CTCL. One CR (duration > 20 months) in a patient with NHL (Lennett's lymphoma) and two PR (duration 9 and 2 months) in 17 patients with B-cell NHL have been observed. Based on the mode of action of DAB389IL-2, its safety profile, and the patient responses associated with the phase I/II clinical trials, a phase III programme in CTCL patients has been initiated and plans for additional trials in NHL patients are targeted for 1996.

Effects of intravenous methylnaltrexone on opioid-induced gut motility and transit time changes in subjects receiving chronic methadone therapy: a pilot study.

In this preliminary study, we evaluated the effects of methylnaltrexone, a peripheral opioid-receptor antagonist, on chronic opioid-induced gut motility and transit changes in four subjects with chronic methadone-induced constipation. Subjects participated in this single blind, placebo controlled study for up to 8 days. We gave placebo the first day; for the remainder of the study, we gave intravenous methylnaltrexone (0.05-0.45 mg/kg) twice daily. During the study period, we recorded oral-cecal transit time and opioid withdrawal symptoms, as well as laxation response based on the frequency and consistency of the stools. Subjects 1 and 2 who were administered methylnaltrexone 0.45 mg/kg, a dose previously administered in normal volunteers, showed immediate positive laxation. Subject 2, after positive laxation response, had severe abdominal cramping, but showed no opioid systemic signs of withdrawal. The subject was discontinued due to the cramping. In Subjects 3 and 4, we reduced the methylnaltrexone dose to 0.05-0.15 mg/kg. The latter two subjects also had an immediate laxation response during and after intravenous medication without significant side effects. The stool frequency of these four subjects increased from 1-2 times per week before the study to approximately 1.5 stool per day during the treatment period. Oral-cecal transit times of Subjects 1, 3, and 4 were reduced from 150, 150 and 150 min (after placebo) to 90, 60 and 60 min (with methylnaltrexone), respectively. Our preliminary results demonstrate that low dose intravenous methylnaltrexone effectively reversed chronic methadone-induced constipation and delay in gut transit time. Thus, we anticipate that cancer patients receiving chronic opioids may also have increased sensitivity to methylnaltrexone, and that low dose methylnaltrexone may have clinical utility in managing opioid-induced constipation in chronic-pain patients.