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.

Outcomes of auto-SCT for lymphoma in subjects aged 70 years and over

The safety and efficacy of auto-SCT for lymphoma in older patients is not well established, particularly in those ≥70 years old. We performed a retrospective analysis comparing 17 auto-SCT recipients ≥70 years old with 39 recipients aged 65-69 years. Hematopoietic cell transplantation comorbidity index (HCT-CI) scores were similar in both groups. Nonrelapse mortality (NRM) was increased in patients aged 70 years and older (hazard ratio (HR) 6.04, P=0.0029), and OS was decreased (HR 1.98, P=0.082). 1-year NRM was 35% in patients aged ≥70 years vs 8% in those aged 65-69 years (P=0.017). The incidence of in-hospital falls was higher in those aged ≥70 years (29 vs 8%, P=0.047). In a secondary exploratory analysis, we found that the occurrence of in-hospital falls was strongly associated with inferior OS (HR 3.36, P=0.0023) and NRM (HR 4.60, P=0.009) among all patients of aged 65 years and older. We conclude that auto-SCT is feasible in older patients but that mortality rates appear increased in those over age of 70 years. In-hospital falls were correlated with higher mortality, and prevention of falls may improve outcomes. Susceptibility to falls may indicate underlying frailty and should be explored prospectively as a means of selecting older patients for auto-SCT.

Long-term treatment of CTCL with the oral PNP inhibitor, forodesine

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Background: Forodesine is a potent inhibitor of purine nucleoside phosphorylase (PNP) that leads to T-cell selective intracellular accumulation of dGTP, resulting in apoptosis. Methods: An open-label dose escalation study of oral forodesine (40–320 mg/m2 daily) for 4 wks with extended therapy was performed to determine the maximum tolerated and/or optimal biologic dose (OBD). Additional subjects were accrued at an OBD (80 mg/m2) to further assess safety and clinical efficacy. Subjects with refractory CTCL, stages IB-IV were eligible. The primary efficacy endpoint (objective response rate [ORR]) was defined as ≥ 50% improvement by a severity-weighted assessment tool (mSWAT). Results: The overall intent to treat response rate was 17 of 64 (27%) subjects or 14 of 36 (39%) at the OBD. As of October 2008, nine of 64 subjects (14%) have received forodesine treatment for >12 months. This cohort of 9 subjects is further examined. Six discontinued treatment (median time on treatment 440 days): 4 for progressive disease, 1 withdrew consent, and 1 due to an adverse event (Diffuse Large B-cell Lymphoma). Three are continuing on therapy for 416, 710, and 863 days. Median age was 68 years (range 42, 81), and all but one was ≥ stage III. They had received a median of 3 prior systemic therapies including 8 of 9 with prior bexarotene. Five of 9 subjects had a response (2 with complete response, 3 with partial response, and 4 with stable disease). Related AEs were experienced by 7 of 9 subjects. The most frequent were nausea (44%), fatigue, peripheral edema, dyspnea, and urinary casts (all 22%). Grade 3 or higher related AEs were experienced by 2 of 9 subjects (Diffuse Large B-Cell Lymphoma as previously mentioned and peripheral edema). There were no hematologic or infection AEs related to forodesine. Grade 3 lymphopenia and CD4 count < 200 were noted in 8 of 9 and 4 of 9 subjects respectively. The risk of any infection AE regardless of cause in these 9 subjects was 15 per 100 person-months of forodesine exposure compared to 59 in all other subjects (n=55). Conclusions: Forodesine has an acceptable safety profile and efficacy in these CTCL subjects treated for 12 months or longer.

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PROPEL: Results of the pivotal, multicenter, phase II study of pralatrexate in patients with relapsed or refractory peripheral T-cell lymphoma (PTCL)

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Background: Pralatrexate is a novel targeted antifolate designed to accumulate preferentially in cancer cells. PROPEL, a pivotal phase 2, non-randomized, open-label, international study, is the largest prospective study in patients (pts) with relapsed or refractory PTCL. Methods: Pts received 30 mg/m2 of pralatrexate intravenously weekly for 6 of 7 weeks, supplemented with B12 and folic acid. Primary endpoint = objective response rate (ORR); secondary endpoints = response duration, progression-free survival, and overall survival. Eligibility criteria: histologically confirmed PTCL, disease progression after ≥ 1 prior treatment, and ECOG performance status ≤ 2. Pathology was confirmed by independent central review, response to therapy was assessed by independent central review using International Workshop Criteria (IWC). Results: 115 pts were enrolled, 109 were evaluable for efficacy. 111 treated pts included 76 males (68%) and 35 females (32%). Pts had failed a median of 3 prior regimens and thus were heavily pre-treated. 78 pts (70%) failed CHOP, 18 (16%) had previous autologous stem cell transplant. 25% of pts never responded to any prior therapy; 53% did not respond to last prior therapy. The majority (59 pts, 53%) had PTCL not-otherwise specified. The ORR by central review was 27% (n = 29). 11 pts (10% overall, 38% of responders) had a complete response (CR), 18 pts (17%) had a partial response (PR), and 23 (21%) had stable disease. ORR by investigators assessment was 39% (n = 42). The median duration of response cannot be accurately estimated at this time, though responses of > 1 year have been observed. 69% of responses were after just 1 cycle. 5 responding pts went on to transplant. The most frequent Grade (Gr) 3–4 adverse events were mucosal inflammation (Gr 3 = 17%, Gr 4 = 4%) and thrombocytopenia (Gr 3 = 14%, Gr 4 = 19%). Conclusions: The results of PROPEL show that pralatrexate exhibits substantial activity in pts with relapsed or refractory PTCL, as assessed by a rigorous central review, with durable CRs /PRs, irrespective of the amount of prior therapy.

[Table: see text]

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.

Immunogenetic analysis of bone marrow aspirates in patients with non-Hodgkin lymphomas

The immunogenetic analysis (IGA) on the staging bone marrow aspirates in 15 patients with non-Hodgkin lymphoma (NHL) is reported. We found the sensitivity of IGA and morphologic examination in detecting bone marrow involvement by malignant lymphoma to be 91% and 82%, respectively. In 11 cases there was agreement between the morphologic findings and IGA. In 8 of these 11 cases, IGA confirmed the morphologic involvement of the bone marrow by demonstrating clonal rearrangement of either the immunoglobulin heavy- and/or light-chain or the T-cell receptor beta chain (TCR) genes. In 3 of these 11 cases, morphology showed no involvement and IGA showed germline configurations for both the immunoglobulin heavy- and light-chain or the TCR genes. In 2 additional cases the techniques proved to be complementary, as involvement was detected by only 1 of the 2 procedures. In 1 of these 2 cases, IGA showed gene rearrangement while morphologic examination was negative for involvement by NHL, while in the other case, morphologic examination showed involvement by NHL, but IGA did not show gene rearrangement. IGA was also useful in determining the clonality of solitary lymphoid nodules in the 2 remaining cases when morphologic interpretation was equivocal. In the 12 cases with bone marrow involvement, the immunophenotype and immunogenotype agreed in 11 cases. In the one case in which there was a discordance between the immunophenotype and immunogenotype, the immunophenotype was incorrectly interpreted as B-cell lineage, while the immunogenotype demonstrated a T-cell lineage. IGA also demonstrated a clonal population in 1 case of T-chronic lymphocytic leukemia where other techniques could not demonstrate the clonality of the pathologic process. IGA analysis may detect bone marrow involvement in NHL which may not be detected by morphologic examination because of patchy distribution.

Acute hepatic injury after the withdrawal of immunosuppressive chemotherapy in patients with hepatitis B

Five patients with lymphoproliferative malignancies and chronic hepatitis B suffered severe acute hepatic injury after the withdrawal of multiagent chemotherapy that included high-dose corticosteroid. Four patients died of hepatic failure, three of whom received corticosteroid as treatment for the hepatic injury. We believe that the cause of this entity is massive immune-associated cytolysis of hepatitis B virus infected hepatocytes occurring after a period of immunosuppression and increased viral replication. The literature regarding this complication of chemotherapy and its pathophysiology is reviewed.

Third-World Hodgkin's disease at Los Angeles County-University of Southern California Medical Center

The reported experience with Hodgkin's disease (HD) in the United States has come primarily from large referral centers that attract a predominantly white population of high socioeconomic status (SES). The majority of these patients had the nodular sclerosis (NS) histologic subtype and asymptomatic stage I/II disease. We have reviewed the records of 178 patients with HD seen within the past 17 years at Los Angeles County-University of Southern California Medical Center (LAC/USC), which is a nonreferral, government-operated facility. Our patient population was found to be heterogeneous, with 38% white, 22% black, and 36% Hispanic. Systemic "B" symptoms were noted in 62% of patients at diagnosis, and 63% had advanced disease (stage III or IV). NS pathologic subtype was present in only 52% of the group. Comparison between the races revealed: (1) Hispanics had a higher incidence of lymphocyte depleted subtype and less NS than whites (P less than .06); (2) whites had equal distribution between stages I/II and III/IV; (3) blacks and Hispanics presented more frequently with stage III/IV (P = .10); and (4) extranodal involvement occurred most often in bone in whites, and was equally distributed between liver, lung, and bone in blacks and Hispanics. We conclude that the lower SES, mixed racial population seen at our institution more closely resembles the reports of HD in Third-World countries and is characterized by advanced symptomatic disease. Further, the clinical pathologic characteristics of HD in the United States may vary significantly, depending upon the precise ethnic and socioeconomic status of the patients being served.