Plain Language Summary of the iNNOVATE study: ibrutinib plus rituximab is well-tolerated and effective in people with Waldenström's macroglobulinemia

WHAT IS THIS SUMMARY ABOUT?

This article provides a short summary of 5-year results from the iNNOVATE trial. The original paper was published in the Journal of Clinical Oncology in October 2021. People with Waldenström's macroglobulinemia (WM) were randomly divided into two groups of 75 people each. One group received a combination treatment composed of two drugs, ibrutinib plus rituximab, and the other group took placebo ("sugar pill") plus rituximab. Ibrutinib (also known by the brand name Imbruvica^®) is a drug that reduces cancer cells' ability to multiply and survive. Ibrutinib is an FDA-approved drug for the treatment of WM. Rituximab is a drug that helps the immune system find and kill cancer cells. Participants in the trial were treated and their health monitored for up to 5 years (63 months).

WHAT WERE THE RESULTS?

During the 5 years of monitoring, more people who took ibrutinib plus rituximab experienced an improvement in their disease and lived longer without their disease getting worse compared to those who took placebo plus rituximab. Side effects from ibrutinib and rituximab were manageable and generally decreased over time. Participants in both study groups reported improvements in quality of life, but those who took ibrutinib plus rituximab reported significantly greater improvement in their quality of life (as measured by FACT-An score) compared to those who took placebo plus rituximab.

WHAT DO THE RESULTS MEAN?

These results show that ibrutinib plus rituximab is better than rituximab alone in people with WM and that ibrutinib plus rituximab is safe and effective in the long term. This information confirms the role of ibrutinib plus rituximab as a standard of care for WM. Clinical Trial Registration: NCT02165397 (ClinicalTrials.gov).

Ibrutinib Plus Rituximab Versus Placebo Plus Rituximab for Waldenström's Macroglobulinemia: Final Analysis From the Randomized Phase III iNNOVATE Study

PURPOSE

The double-blind, randomized, placebo-controlled phase III iNNOVATE study showed sustained efficacy of ibrutinib-rituximab in Waldenström's macroglobulinemia (WM). Here, we present the final analysis from iNNOVATE.

METHODS

Patients had confirmed symptomatic WM, either previously untreated or previously treated; patients with prior rituximab had at least a minor response to their last rituximab-based regimen. Patients were randomly assigned to once-daily ibrutinib 420 mg plus rituximab or placebo plus rituximab (n = 75 per arm). The primary end point was progression-free survival (PFS). Secondary end points included response rate, time to next treatment, hemoglobin improvement, overall survival, and safety.

RESULTS

With a median follow-up of 50 (range, 0.5-63) months, median (95% CI) PFS was not reached (57.7 months to not evaluable) with ibrutinib-rituximab versus 20.3 months (13.0 to 27.6) with placebo-rituximab (hazard ratio, 0.250; P < .0001). PFS benefit was regardless of prior treatment status, MYD88 and CXCR4 mutation status, or key patient characteristics. Higher response rates (partial response or better) were observed with ibrutinib-rituximab (76% v 31% with placebo-rituximab; P < .0001) and were sustained over time. Median time to next treatment was not reached with ibrutinib-rituximab versus 18 months with placebo-rituximab. More patients receiving ibrutinib-rituximab versus placebo-rituximab had sustained hemoglobin improvement (77% v 43%; P < .0001). Median overall survival was not reached in either arm. Ibrutinib-rituximab maintained a manageable safety profile; the prevalence of grade ≥ 3 adverse events of clinical interest generally decreased over time.

CONCLUSION

In the final analysis of iNNOVATE with a median follow-up of 50 months, ibrutinib-rituximab showed ongoing superiority across clinical outcomes in patients with WM regardless of MYD88 or CXCR4 mutation status, prior treatment, and key patient characteristics.

A phase 2 study of ibrutinib in combination with bortezomib and dexamethasone in patients with relapsed/refractory multiple myeloma

Objective

We evaluated ibrutinib, a once‐daily inhibitor of Bruton's tyrosine kinase, combined with bortezomib and dexamethasone in patients with relapsed or relapsed/refractory multiple myeloma who had received 1‐3 prior therapies.

Methods

This was a phase 2, single‐arm, open‐label, multicentre study (NCT02902965). The primary endpoint was progression‐free survival (PFS).

Results

Seventy‐six patients were enrolled; 74 received ≥1 dose of study treatment. After median follow‐up of 19.6 months, median PFS was 8.5 months (95% CI: 6.2‐10.8); median overall survival was not reached. Overall response rate was 57% (95% CI: 45‐68), and median duration of response was 9.5 months (95% CI: 6.9‐10.6). Grade 3/4 AEs occurred in 73% of patients and fatal AEs occurred in 15% of patients. Incidence of major haemorrhage was 5%; one patient died from cerebral haemorrhage. After an observed increased incidence of serious (42%) and fatal (11%) infections, enrolment was suspended to implement risk‐minimisation measures. The safety profile was otherwise consistent with known safety profiles of the individual drugs.

Conclusion

Ibrutinib combined with bortezomib and dexamethasone elicited clinical responses. However, efficacy assessments conducted at potential restart of enrolment indicated that the targeted PFS could not be reached with additional patient enrolment, and the study was terminated.

Patient-reported outcomes (PROs) with ibrutinib-rituximab in Waldenström macroglobulinemia (WM): Results from iNNOVATE

8018

Background: Anemia and fatigue can impair quality of life in patients (pts) with WM. Ibrutinib (ibr) as single agent or in combination with RTX is FDA-approved for WM. In pts with RTX-refractory WM, single-agent ibr induced meaningful improvements in PROs (Trotman, EHA 2017). In iNNOVATE, ibr-RTX (IR) produced higher rates of sustained hemoglobin improvement and meaningful improvements in PROs versus placebo-RTX (R; Dimopoulos NEJM 2018). Here, we report detailed PRO analyses from iNNOVATE. Methods: Pts with symptomatic WM requiring therapy were randomized to daily 420 mg oral ibr or placebo, both with RTX (375 mg/m2/week IV at weeks 1–4 and 17–20). PRO measures included FACIT-Fatigue (FACIT-F), FACT-An total score (TS) and anemia subscale score (AS), and EQ-5D-5L (EuroQol Research Foundation. EQ-5D is a trade mark of the EuroQol Research Foundation) visual analog scale (VAS), and utility score (US). Results: For 150 randomized pts (n=75/arm), most common reasons for initiating therapy were fatigue (61%), constitutional symptoms (32%), and anemia (32%). Baseline PRO scores were comparable in both arms. At a median follow-up of 26.5 mo, numerically more pts showed clinically meaningful improvement in FACIT-F, TS, and AS with IR than R (Table). Median time to PRO improvement was short (1-2 mo) in both arms. At week 25, the Pearson correlation coefficients were 0.28, 0.29, and 0.26 for changes in hemoglobin levels vs changes in FACIT-F, TS and AS, respectively, in the IR arm; no meaningful correlations were observed on R. The correlation coefficients were -0.32, -0.33, -0.35 and -0.26 for changes in IgM levels vs changes in FACIT-F, TS, AS, and EQ-VAS, respectively, for IR and 0.29 and 0.35 vs FACIT-F and TS for R. Conclusions: Clinical response and improvements in anemia with IR are consistent with more pts showing clinically meaningful improvement in PROs versus R. Changes in IgM correlate with improvements in PROs. Clinical trial information: NCT02165397. [Table: see text]

A randomized, double-blind phase III study of ibrutinib versus placebo in combination with corticosteroids in patients with new onset chronic graft versus host disease

TPS7072

Background: Chronic graft versus host disease (cGVHD) is a common complication of allogeneic stem cell transplantation, with pathophysiology involving alloreactive and dysregulated T and B cells and innate immune populations. Ibrutinib, a first-in-class, once-daily inhibitor of Bruton's tyrosine kinase, is indicated by the US FDA for the treatment of patients (pts) with CLL/SLL. Ibrutinib recently received breakthrough therapy and orphan drug designation for the treatment of pts with cGVHD who did not respond to one or more lines of systemic therapy. Ibrutinib reduces severity of cGVHD in murine models and recently was shown to achieve an NIH-defined overall response rate of 67% in pts with steroid relapsed/refractory cGVHD (Miklos Blood 2016). Methods: The primary objective of this Phase 3, multicenter, international, randomized, controlled, double-blind study is to evaluate the 24-week response rate of ibrutinib versus placebo in combination with prednisone. Pts with newly diagnosed moderate or severe cGVHD, as per NIH Consensus Development Project Criteria (2014), will be randomized in a 1:1 ratio to receive either oral ibrutinib (arm A) or placebo (arm B) in combination with oral prednisone. Ibrutinib or placebo will be given until unacceptable toxicity, relapse of underlying disease, death, or the need for a new systemic treatment for progressive cGVHD. Eligible study pts (age ≥12 yrs) must require systemic treatment with corticosteroids and have no prior systemic treatment for cGVHD. The primary endpoint is response rate (complete or partial response) at 24 weeks, as per NIH Consensus Development Project Criteria, and must occur in the absence of both new therapy for cGVHD and relapse/return of the underlying disease that was the indication for transplant. Secondary endpoints will assess for additional clinical benefit including corticosteroid dose reduction, improvement of Lee cGVHD Symptom Scale scores, withdrawal of all immunosuppressants, and overall survival. This study is currently enrolling pts. Funding source: Pharmacyclics LLC, an AbbVie Company. Clinical trial information: NCT02959944.

Resminostat plus sorafenib as second-line therapy of advanced hepatocellular carcinoma - The SHELTER study

BACKGROUND & AIMS

No established therapies for patients with hepatocellular carcinoma (HCC) and progression on first-line sorafenib treatment currently exist. This phase I/II trial investigated safety, pharmacokinetics and potential biomarkers of the histone deacetylase inhibitor resminostat and a combination therapy with resminostat and sorafenib.

METHODS

Patients with HCC and radiologically confirmed progression on sorafenib were treated in an exploratory, multi-center, open-label, uncontrolled, non-randomized, parallel group phase I/II study. In the combination group (n=38) four dose levels ranged from daily 200 to 600mg resminostat plus 400 to 800mg sorafenib. The monotherapy group (n=19) received 600mg resminostat.

RESULTS

57 patients received treatment. Most common adverse events were gastrointestinal disorders, thrombocytopenia and fatigue. Median maximal histone deacetylase inhibition and highest increase in H4-acetylation matched Tmax of resminostat. Sorafenib or the Child-Pugh score did not affect typical pharmacokinetics characteristics of resminostat. Efficacy assessment as progression-free survival-rate after 6 treatment cycles (12weeks, primary endpoint) was 12.5% for resminostat and 62.5% for resminostat plus sorafenib. Median time to progression and overall survival were 1.8 and 4.1months for resminostat and 6.5 and 8.0months for the combination, respectively. Zinc finger protein 64 (ZFP64) baseline expression in blood cells was found to correlate with overall survival.

CONCLUSIONS

The combination of sorafenib and resminostat in HCC patients was safe and showed early signs of efficacy. Sorafenib did not alter the pharmacokinetic profile of resminostat or its histone deacetylase inhibitory activity in vivo. A prognostic and potentially predictive role of ZFP64 for treatment with resminostat should be further investigated in HCC and possibly other cancer indications.

LAY SUMMARY

No established therapy for patients with advanced hepatocellular carcinoma and progression under first-line systemic treatment with sorafenib currently exists. Epigenetic modulation by inhibition of histone deacetylases might be able to overcome therapy resistance. This exploratory phase I/II clinical study in patients with radiologically confirmed progression under first-line treatment with sorafenib investigated the histone deacetylases inhibitor resminostat as single agent or in combination with continued application of sorafenib.

CLINICAL TRIAL REGISTRATION

The clinical trial has been registered at www.clinicaltrials.gov as NCT00943449.

First-in-human, pharmacokinetic and pharmacodynamic phase I study of Resminostat, an oral histone deacetylase inhibitor, in patients with advanced solid tumors

PURPOSE

This first-in-human dose-escalating trial investigated the safety, tolerability, maximum tolerated dose (MTD), dose-limiting toxicities (DLT), pharmacokinetics, and pharmacodynamics of the novel histone deacetylase (HDAC) inhibitor resminostat in patients with advanced solid tumors.

EXPERIMENTAL DESIGN

Resminostat was administered orally once-daily on days 1 to 5 every 14 days at 5 dose levels between 100 and 800 mg. Safety, pharmacokinetics, pharmacodynamics including histone acetylation and HDAC enzyme activity, and antitumor efficacy were assessed.

RESULTS

Nineteen patients (median age 58 years, range 39-70) were treated. At 800 mg, 1 patient experienced grade 3 nausea and vomiting, grade 2 liver enzyme elevation, and grade 1 hypokalemia and thrombocytopenia; these were declared as a combined DLT. No other DLT was observed. Although an MTD was not reached and patients were safely dosed up to 800 mg, 3 of 7 patients treated with 800 mg underwent dose reductions after the DLT-defining period due to cumulative gastrointestinal toxicities and fatigue. All toxicities resolved following drug cessation. No grade 4 treatment-related adverse event was observed. The pharmacokinetic profile was dose-proportional with low inter-patient variability. Pharmacodynamic inhibition of HDAC enzyme was dose-dependent and reached 100% at doses ≥400 mg. Eleven heavily pretreated patients had stable disease and 1 patient with metastatic thymoma had a 27% reduction in target lesion dimensions.

CONCLUSIONS

Resminostat was safely administered with a dose-proportional pharmacokinetic profile, optimal on-target pharmacodynamic activity at dose levels ≥400 mg and signs of antitumor efficacy. The recommended phase II dose is 600 mg once-daily on days 1 to 5 every 14 days.

Phase I dose escalation of the oral histone deacetylase inhibitor (HDACi) resminostat in combination with FOLFIRI in colorectal cancer (CRC) patients: The SHORE trial

3625

Background: Resminostat is a novel oral HDAC inhibitor with broad activity in various cancer models. In CRC models, resminostat revealed synergistic effects with 5-FU and irinotecan/SN-38, indicating its (re-)sensitization potential when applied in combination therapy. Furthermore, resminostat downregulates thymidylate synthase, involved in drug resistance to 5-FU and effectively inhibits HDAC2, one of the target enzymes believed to critically support development of CRC. The phase I/II SHORE trial investigates resminostat in combination with FOLFIRI in patients previously treated with 5-FU. Methods: Patients (pts) with advanced CRC having previously received 5-FU alone or in combination with other agents who were scheduled for FOLFIRI in second or later treatment lines were included. The phase I comprised an open-label, inter-patient, ‘3+3’ dose escalation design with increasing doses of resminostat combined with standard FOLFIRI. Pts received resminostat on 5 consecutive days, followed by a 9-day drug free period (‘5+9’ scheme, i.e. 14-day cycles). On days 3 and 4 of each cycle (C), FOLFIRI was administered. Primary objective of the Phase I part was to determine safety and tolerability, the maximum tolerated dose and pharmacokinetics of the combination. Results: 17 pts (median age 61 yrs; 12 males; 11 ECOG 0; 6 ECOG 1; median therapy line 2 [2-6]) were enrolled in 4 dose levels of resminostat 200, 400, 600 mg QD (3 pts each) and 400 mg BID (6 pts) plus FOLFIRI. Two pts discontinued in C1 and were replaced. No DLT occurred. AEs consisted mainly of GI symptoms of mild and moderate intensity (nausea, vomiting and diarrhea) leading to decreased electrolyte plasma levels in some pts. In the highest dose level tested (400 mg BID) hematological toxicity, mainly neutropenia up to grade 4, was observed leading to dose reductions in 3 pts in C3 and C7. No objective responses were reported, however some pts showed SD for prolonged time (up to 32 w). Results of the completed phase I part will be reported. Conclusions: The combination of resminostat with standard FOLFIRI was safe and well tolerated warranting continuation into the Phase II part of the study. Clinical trial information: NCT01277406.

Resminostat in advanced hepatocellular carcinoma (HCC): Overall survival subgroup analysis of prognostic factors in the SHELTER trial

e15088

Background: Previously published results of the phase I/II SHELTER study demonstrated efficacy and safety of the novel pan-HDAC inhibitor resminostat in second-line treatment of HCC patients (pts) who had progressed under first-line sorafenib. As patient baseline characteristics might influence treatment outcome, an analysis of their potential influence on overall survival (OS) was performed. Methods: 45 pts with advanced-stage HCC and centrally confirmed radiologic progression under first-line sorafenib were included in a multi-center, two-arm trial. Resminostat was administered either alone or in combination with sorafenib. A Cox proportional-hazards model was used to evaluate the interaction between baseline characteristics and the effect of the two treatment groups on overall survival. Results: In the combination group, pts with Child-Pugh-A, ECOG 0 or absence of vascular invasion had a statistically significant lower risk of death compared to pts with Child-Pugh-B (HR 0.19, 95% CI 0.06-0.55), ECOG 1 (HR 0.15, 95% CI 0.05-0.44), or vascular invasion (HR 0.37, 95% CI 0.15-0.93), respectively. For pts with BCLC-B there was a strong trend, although not statistically significant, of a lower risk of death when compared to pts with BCLC-C (HR 0.43, 95% CI 0.13-1.49). Etiology, prior TACE therapy, extrahepatic spread and interval between first- and second-line treatment had no impact on overall survival in this study. Similar findings were observed in the monotherapy group. Comparing the impact of these baseline characteristics in the combination and monotherapy group, no statistically significant different influence on OS between both treatment groups was observed. Conclusions: Resminostat in combination with sorafenib provides a substantial OS benefit (median OS of 8.1 months) for advanced HCC patients who had developed progressive tumor disease under first-line sorafenib therapy. Subgroup analysis of patient baseline characteristics revealed a significant influence of Child-Pugh index, ECOG classification, and vascular invasion on overall survival, whereas e.g. the interval between first- and second-line treatment had no impact on overall survival. Clinical trial information: NCT00943449.

Efficacy, safety, tolerability, and PK of the HDAC inhibitor resminostat in sorafenib-refractory hepatocellular carcinoma (HCC): Phase II SHELTER study

4115

Background: Resminostat (R), an oral HDAC inhibitor, was studied in the SHELTER trial evaluating safety, PK and efficacy in HCC patients (pts) refractory to sorafenib (S). R was explored as monotherapy and within a novel resensitization approach to overcome tolerance to S by the combination of both drugs. Methods: Pts with advanced HCC (BCLC B/C) were included in a multi-center, two-arm trial. Radiologic progression under S firstline therapy had to be confirmed by central review (RECIST) prior to study entry. A dose escalation of R (range 200 to 600 mg) combined with S (400 or 800 mg) was performed. Arm A investigated the drug combination (R+S), Arm B the monotherapy of R (600 mg). Primary objective was the progression-free survival rate (PFSR) after 12 weeks (w). Secondary objectives included safety, tolerability, tumor response, PFS, TTP, OS and the analyses of PK and biomarkers (BM), incl. AFP, VEGF, HDAC enzyme inhibition, histone acetylation and gene expressions in peripheral blood. Results: 50 pts were enrolled, dose escalation determined 600 mg R and 400 mg S for Arm A. Clinical activity results of 15 evaluable pts from combination treatment revealing a PFSR of 66.6% after 12 w, not all patients in Arm B already reached the 12 w staging. Most frequent AE were CTC grade 1-2 GI complaints (nausea, vomiting) and skin disorders (rash, pruritus, HFSR). Grade 3-4 toxicity (SAE reports) consisted mainly of non-hematological events mostly related to tumor disease. Plasma concentrations of both drugs correlated with administered doses and were in the expected range without obvious influence of preexisting liver disease. BM investigations revealed effective target modulation by R in both arms. Conclusions: The primary study objective was achieved for both treatment arms. R demonstrated a favorable PK, safety and tolerability profile, even in combination with S and despite preexisting liver disease, includig cirrhosis. The observed clinical activity emphazises the resensitizing activity of R by an epigenetic mode-of-action to overcome tolerance to S and warrants further development, in particular for combination therapy in both, first and second line HCC treatment.

Investigation of the HDAC inhibitor resminostat in patients with sorafenib-resistant hepatocellular carcinoma (HCC): Clinical data from the phase I/II SHELTER study

262

Background: Resminostat (4SC-201), an oral pan-HDAC inhibitor, is in clinical development in a variety of cancer indications. The SHELTER study aims to evaluate safety, tolerability and efficacy in HCC patients (pts) exhibiting progressive disease under sorafenib first-line therapy.

Methods: Pts with advanced HCC, (BCLC B or C) are included in a multi-center, open-label, two-arm parallel group trial. Radiologic progression under sorafenib is determined acc. to RECIST by central review prior to study entry. For Arm A, dose escalation of resminostat and sorafenib is performed to determine the MTD. Resminostat is administered orally once-daily in a “5+9” schedule, consisting of 5 consecutive treatment days followed by a 9-day rest period resulting in 14 day cycles on dose levels of 200 (DL1), 400 (DL2) and 600 mg (DL3+4), either combined with continuously taken sorafenib at 400 (DL1-3) or 800 mg (DL4) (Arm A), or as resminostat monotherapy (600 mg, Arm B). Primary objective is to determine progression-free survival after 12 weeks (w) (6 cycles). Secondary objectives include safety, tolerability, tumor response, TTP, OS, PK, biomarkers.

Results: To date, 39 pts were treated with 600 mg resminostat alone or on DL1-4 in combination with sorafenib. Up to now, no DLT occurred in 5 pts treated on DL4. Most frequently AE observed include CTC grade 1-2 gastrointestinal complaints such as nausea and vomiting and skin disorders like rash, pruritus and HFSR. CTC Grade 3-4 toxicity documented in SAE reports consisted mainly of no-hematological events and was mostly related to the tumor disease. Interim results revealed that 15 out of 27 pts (56%) assessed after 6 w of treatment, and 11 out of 24 pts after 12 w displayed SD. In one patient treated on DL2, SD persisted for more than 1 year along with good long-term tolerability.

Conclusions: Preliminary clinical data show a favorable drug profile of resminostat either in mono or in combination treatment with sorafenib. No DLT was observed on the highest DL of the combination therapy up to now. Initial data on toxicity and therapeutic activity to overcome resistance to sorafenib are promising and will be updated for the meeting.

Clinical update on the SHELTER study: A phase I/II trial of the HDAC inhibitor resminostat in patients with sorafenib-resistant hepatocellular carcinoma (HCC)

275

Background: Resminostat (4SC-201) is a novel oral pan-HDAC inhibitor in clinical development in a variety of cancer indications. The aim of the SHELTER study is to evaluate safety, tolerability, and efficacy in patients (pts) with HCC exhibiting progressive disease under sorafenib first-line therapy.

Methods: Sorafenib-refractory pts with advanced HCC, BCLC B or C are included in a multicenter, open-label, two-arm parallel group trial. Resminostat is administered orally on three dose levels of 200 (DL1), 400 (DL2), and 600 mg (DL3) once daily, in combination with 400 mg sorafenib (arm A) or as mono therapy (600 mg, arm B). For arm A, a precedent dose escalation of resminostat and sorafenib is performed to determine the MTD. Resminostat is administered in a “5+9” dosing schedule, consisting of 5 consecutive treatment days (D1-5) followed by a 9-day rest period resulting in 14 day cycles. In arm A sorafenib is given twice daily throughout the treatment period. Primary objective is to determine progression-free survival rate after 12 weeks (6 cycles). Secondary objectives include safety and tolerability, tumor response, estimation of TTP, OS, assessment of PK, and biomarkers.

Results: To date, 14 pts were treated either with 600 mg resminostat alone or on DL1-3 in combination with 400 mg sorafenib. The majority of AE observed so far include gastrointestinal disorders such as nausea and vomiting. Plasma exposure to resminostat increased dose-dependently on D1 (cycle 1) with mean AUC 0-6 h values of 10.5 h*mg/L (600 mg mono) and 9.01 h*mg/L (DL3). No major changes in PK characteristics of resminostat were found with or without co-administration of sorafenib. A considerable portion of patients showed stabilization of their disease (SD): 9 out of 12 pts and 4 out of 5 pts examined after 6 and 12 weeks, respectively, displayed SD. In one patient treated on DL2, SD persisted for 36 weeks along with good long-term tolerability.

Conclusions: Preliminary clinical data confirmed the favorable oral drug profile of resminostat either in mono or in combination treatment with sorafenib. Initial data on therapeutic activity to overcome resistance to sorafenib are promising.

[Table: see text]

A first-in-human phase I study of 4SC-201, an oral histone deacetylase (HDAC) inhibitor, in patients with advanced solid tumors

3530

Background: 4SC-201 (former code BYK408740) is a specific, potent, pan-HDAC inhibitor with improved ADME properties. Methods: Patients (pts) with advanced refractory solid tumors were dosed once daily (QD) d1–5 in a 14-day cycle in sequential cohorts of 3–6 pts with 50 or 100% dose increments. Primary objectives were to determine safety, tolerability, pharmacokinetics (PK) and maximum tolerated dose (MTD) of 4SC-201. Pharmacodynamic assessment (histone acetylation and HDAC enzyme activity) and anti-tumor efficacy were secondary objectives. Blood samples for PK and PD were taken on days 1, 5 and 47 of treatment. Results: 18 pts (9M/9F) with a median age of 58.5 yrs (range 40–70) were treated at five dose levels: 3 pts each at 100mg, 200mg, 400mg and 600mg and 6 pts at 800mg. All pts were evaluable for toxicity and received at least 2 treatment cycles. Grade 3 DLT of nausea and vomiting occurred in 1 pt dosed at 800mg. Most common adverse events included nausea, vomiting and fatigue. 8 of 9 pts treated in the 600mg and 800mg cohorts had stable disease during the main phase of the study (4 treatment cycles). A patient with liposarcoma and another with thymoma (marginal response) continued treatment beyond 6 months. PK parameters were dose-proportional with a low inter-individual variability and indicated good bioavailability. The apparent t1/2 of oral 4SC-201 ranged from 2.3 to 4.4 hours. The degree of HDAC inhibition measured in a peripheral blood mononuclear cell functional assay was dose- dependent and increased from 50 to 100 %, although histone H4 acetylation accumulation after dosing did not differ significantly between dose levels. Conclusions: Oral 4SC-201 has favorable disposition and can be safely administered; 600mg QD d1–5 in a 14-day cycle is recommended for phase II evaluation. Safely administered doses modulate target with antitumor activity.

[Table: see text]

The oral, once-daily phosphodiesterase 4 inhibitor roflumilast lacks relevant pharmacokinetic interactions with inhaled budesonide

This open-label, randomized, 3-period crossover study evaluated the pharmacokinetic interaction potential of roflumilast and budesonide following repeated coadministration to healthy male subjects (N = 12). Treatments consisted of oral roflumilast 500 mug, once daily, orally inhaled budesonide 800 mug, twice daily, and concomitant administration of both treatments for 7 days each. Roflumilast and roflumilast N-oxide in plasma and budesonide serum levels were measured by specific assays. Geometric mean test/reference ratios of steady-state pharmacokinetic parameters were evaluated by analysis of variance. Safety and tolerability were monitored. Pharmacokinetic parameters of roflumilast, roflumilast N-oxide, and budesonide after coadministration of roflumilast and budesonide were similar to those after mono-treatment. Compared with budesonide and roflumilast mono-treatments, slightly lower maximum serum/plasma concentration (C(max)) and area under the curve (AUC) values of roflumilast N-oxide and budesonide (ranging from -8% to -16%) were observed with combined treatment. All test/reference ratios were within predefined equivalence acceptance ranges for roflumilast AUC (0.80, 1.25) and C(max) (0.70, 1.43) and for roflumilast N-oxide and budesonide AUC and C(max) (all 0.67, 1.50). Coadministration of roflumilast and budesonide did not alter the steady-state disposition of each other and did not affect safety and tolerability of either drug.

Roflumilast, a once-daily oral phosphodiesterase 4 inhibitor, lacks relevant pharmacokinetic interactions with inhaled salbutamol when co-administered in healthy subjects

OBJECTIVE

Roflumilast is an oral, once-daily phosphodiesterase 4 inhibitor under investigation for the treatment of chronic obstructive pulmonary disease and asthma. In clinical practice, the drug is likely to be co-administered with inhaled bronchodilating beta2-adrenoceptor agonists. Therefore, this study investigated the pharmacokinetic characteristics of roflumilast and its pharmacodynamically active metabolite roflumilast N-oxide when co-administered with orally inhaled salbutamol in healthy subjects.

METHODS

In this open, randomized clinical study, 12 healthy male subjects received repeated doses of oral roflumilast 500 microg once daily, orally inhaled salbutamol 200 microg 3 times daily, and a combination of both drugs over 7 days according to a 3-period, changeover design with 14 days washout between treatments.

RESULTS

Co-administration of roflumilast and salbutamol did not markedly change roflumilast or roflumilast N-oxide disposition. Point estimates (90% confidence intervals) of area under the curve from 0-24 h (AUC 0-24) and maximum plasma concentration in steady state (Cmax,ss) for roflumilast with salbutamol versus roflumilast alone were 1.05 (0.94, 1.17) and 0.97 (0.84, 1.10); the respective point estimates (90% confidence intervals) for AUC 0-24 and Cmax,ss of roflumilast N-oxide were 0.98 (0.91, 1.06) and 0.98 (0.92, 1.03). Roflumilast co-administration did not alter the pharmacokinetics of steady state salbutamol. The respective point estimates (90% confidence intervals) for AUC 0-6 and Cmax,ss of salbutamol with roflumilast versus salbutamol alone were 1.10 (0.99, 1.21), 1.08 (0.91, 1.28). The combination of both drugs was well tolerated.

CONCLUSION

There were no relevant pharmacokinetic interactions between roflumilast and salbutamol at therapeutically effective doses.

Investigation of a potential food effect on the pharmacokinetics of roflumilast, an oral, once-daily phosphodiesterase 4 inhibitor, in healthy subjects

This open, randomized, single-dose crossover study investigated effects of a high-fat meal on the pharmacokinetics of roflumilast and its major active N-oxide metabolite. Twelve healthy subjects received oral roflumilast 500 microg (2 x 250 microg) after overnight fasting and after breakfast. Blood was sampled up to 54 hours for pharmacokinetic profiling of roflumilast and N-oxide. Geometric mean ratios (fed/fasted) for point estimates (PE) and 90% confidence intervals (CI) were calculated for AUC(0-last), AUC(0-infinity), and C(max) of both compounds. After the meal, roflumilast C(max) (PE, 0.59; 90% CI, 0.49-0.70) was modestly reduced; N-oxide C(max) (PE, 0.95; 90% CI, 0.90-1.01) was unchanged. Roflumilast t(max) was delayed in fed state (2.0 +/- 0.4 hours) versus fasted state (1.0 +/- 0.2 hours); N-oxide t(max) was unaltered. No significant food effect on roflumilast AUC(0-last) (PE, 1.04; 90% CI, 0.90-1.21), AUC(0-infinity) (PE, 1.12; 90% CI, 1.00-1.25), and respective N-oxide AUCs (PE, 0.91; 90% CI, 0.79-1.04; PE, 0.99; 90% CI, 0.92-1.06) occurred. Because roflumilast N-oxide is the major contributor to roflumilast's overall pharmacologic effects, these findings suggest that roflumilast can be taken with or without food.

Dose-proportional intraindividual single- and repeated-dose pharmacokinetics of roflumilast, an oral, once-daily phosphodiesterase 4 inhibitor

The dose-proportional, intraindividual, single- and repeated-dose pharmacokinetics of roflumilast, an oral, once-daily phosphodiesterase 4 inhibitor under investigation for chronic obstructive pulmonary disease and asthma, was investigated in healthy subjects. In an open, randomized, 2-period, 2-sequence crossover study, 15 subjects received immediate-release tablets of roflumilast 250 or 500 microg as single (day 1) and as repeated, once-daily doses for 8 days (days 5-12). Dose-adjusted point estimates and 90% confidence intervals of test (500 microg)/reference (250 microg) ratios for AUC and Cmax of roflumilast and its pharmacologically active N-oxide metabolite after single and repeated dosing were all within the standard equivalence acceptance range (0.80, 1.25) indicating dose proportionality. The pharmacokinetic properties of both roflumilast dosage forms provide clinically relevant evidence of predictable, intraindividual total (AUC) and maximum (Cmax) exposure of roflumilast and roflumilast N-oxide. Repeated oral dosing with roflumilast 250 and 500 microg once daily was well tolerated.

Identification and characterization of CYP3A4*20, a novel rare CYP3A4 allele without functional activity

BACKGROUND

The major drug-metabolizing enzyme cytochrome P450 (CYP) 3A4 is genetically conserved. One outlier of Brazilian descent was found in a clinical pharmacokinetic trial exhibiting a 6-fold higher exposure than expected to an investigational drug, shown to be a CYP3A4 substrate. We aimed to investigate the genetic background of this finding.

METHODS

The allelic variant of the CYP3A4 gene present in the outlier was sequenced, and the corresponding complementary deoxyribonucleic acid was expressed in yeast and human embryonic kidney cells. The outlier was phenotyped by use of intravenous administration of 1 mg midazolam. Analysis of phenotype and genotype correlation was carried out. The prevalence of the new allele was screened for in a white population.

RESULTS

We identified a subject who heterozygously carried a novel CYP3A4 allele, named CYP3A4*20, with a premature stop codon yielding a truncated protein. Heterologous expression revealed that the CYP3A4.20 enzyme does not incorporate heme and thus is devoid of catalytic activity. CYP3A phenotyping in vivo showed that CYP3A4*20 exhibits a clear genotype-phenotype correlation, demonstrated by the subject's low systemic midazolam clearance (2.99 mL x min(-1) x kg(-1)). Genotyping of a white German population (n = 428) and relatives of the subject, as well as a review of published CYP3A4 sequencing data, suggests that CYP3A4*20 is a rare variant allele (<0.06% in white subjects).

CONCLUSIONS

CYP3A4*20 represents the first CYP3A4 allele to be identified that has been shown to be devoid of functional activity. It causes an intermediate CYP3A4 metabolizer phenotype in a heterozygous carrier. Subjects of this genotype might be susceptible to side effects during drug therapy with substrates or inhibitors of CYP3A4.

Phase II study of combined 5-fluorouracil/ Ginkgo biloba extract (GBE 761 ONC) therapy in 5-fluorouracil pretreated patients with advanced colorectal cancer

The aim of the study was to evaluate the efficacy, tolerability and quality of life in 5-fluorouracil (5-FU) pretreated colorectal cancer patients after combined 5-FU and Ginkgo biloba extract GBE 761 ONC (i.e. the Ginkgo biloba special extract EGb 761(R)) therapy. Following conventional 5-FU therapy, 44 patients (32 evaluable for response) with advanced progressive colorectal cancer were treated every 3 weeks with courses of 350 mg GBE 761 ONC as a 30 min i.v. infusion on days 1-6 followed by 500 mg/m(2)/d 5-FU as a 30 min i.v. infusion on days 2-6. The response to therapy was evaluated after the second and fourth course of treatment. The data of 32 patients could be evaluated for efficacy. We observed a progression of disease in 22 patients, no change in 8 patients and a partial response in 2 patients (overall response = 6.3%). Seventeen of 22 patients with observed progressive disease showed further progression after two cycles, two after three cycles and three after four cycles. The median survival time was 9.5 months (7.7-11.5 months). GBE 761 ONC was well tolerated. Adverse events that occurred during the study were mainly myelosuppression and gastrointestinal symptoms and were judged to be 5-FU related or consistent with liver toxicity and thus tumour related. Our results suggest a good benefit-risk ratio of the combined 5-FU and GBE 761 ONC therapy as second line treatment in metastatic colorectal cancer. The survival time was similar to that known from second line treatment according to the Ardalan scheme. Since an improvement was observed in some patients despite the failure of the conventional 5-FU pretreatment, it would be interesting to evaluate whether the application of 5-FU plus GBE 761 ONC as a first line treatment is of benefit.

The pharmacokinetics of a 1-h paclitaxel infusion

PURPOSE

To characterize the disposition of paclitaxel (PAC) after a 1-h infusion in humans and define if possible a pharmacodynamic relationship between PAC disposition and the observed toxicity.

PATIENTS AND METHODS

PAC pharmacokinetics were studied in 43 courses of therapy in 30 patients (30 first course, 13 PK third course). PAC was administered at 150, 175, 200, 225 and 250 mg/m2 by a 1-h infusion to patients with advanced cancer (lung, breast, ovarian, cervix, and head and neck). PAC was quantified by high-performance liquid chromatography (HPLC). Pharmacokinetic parameters were calculated by noncompartmental and model-dependent methods.

RESULTS

Increases in the area under the curve and the peak plasma concentration were not proportional to increases in the dose. However, the deviation from linearity is rather moderate. The dose-limiting toxicity was central neuropathy which was not associated with pharmacokinetic deviations. Owing to the absence of grade 3 or 4 myelotoxicity, no clear correlation between this toxicity and pharmacokinetic parameters could be established.

CONCLUSION

Within the evaluated dose range of the 1-h infusion there was only a moderate nonlinear disposition of PAC in humans and therefore a dose of 225 mg/m2 is recommended as safe. The observation of central neuropathy could not be directly related to a pharmacokinetic parameter. The complexity of the formulation which included Cremophor EL and ethanol may offer an explanation for the observed central neurotoxicity.

Phase II study with 5-fluorouracil and ginkgo biloba extract (GBE 761 ONC) in patients with pancreatic cancer

The aim of the study was to evaluate the efficacy and tolerability of as well as the quality of life under treatment with 5-fluorouracil (CAS 51-21-8, 5-FU) combined with parenteral GBE 761 ONC (i.e. the ginkgo biloba special extract EGb 761) in patients with pancreatic cancer. Forty-eight patients with locally or metastatic advanced pancreatic cancer were treated within a phase II study. The treatment was repeated every three weeks until progression. Response to therapy was evaluated after 2 and 4 treatment courses. Thirty-two patients were evaluable for response. Progressive disease was observed in 22 (68.8%) patients, no change in 7 (21.9%) patients and partial response in 3 (9.4%) patients (overall response = 9.4%). GBE 761 ONC was well tolerated. Adverse events which occurred during the study consisted mainly of myelosuppression and gastrointestinal symptoms and were judged as 5-FU-related or consisted of liver toxicity, respectively, and were judged as tumour-related. These results suggest a good benefit-risk ratio of the combination of 5-FU and GBE 761 ONC in the treatment of pancreatic cancer. In comparison with the results of studies with either 5-FU or gemcitabine as single agents the combination of 5-FU/GBE 761 ONC shows comparable response rates. The toxicity of the 5-FU/GBE 761 ONC combination was low. This combination therapy therefore warrants further clinical investigation, such as a controlled clinical trial against 5-FU or gemcitabine monotherapy.

Linearized colorimetric assay for cremophor EL: application to pharmacokinetics after 1-hour paclitaxel infusions

Cremophor EL (CrEL) is a polyoxyethylated castor oil surfactant used in the intravenous formulation of the anticancer drug paclitaxel (Taxol). Quantitative determination of CrEL in patient samples can be achieved by complexation of the compound with the Coomassie brilliant blue G-250 dye in protein-free extracts [Sparreboom, A., Loos, W. J., Verweij, J., De Vos, A. I., Van der Burg, M. E. L., Stoter, G., and Nooter, K., Anal. Biochem. 255, 171-175 (1998)]. A disadvantage of this method of CrEL determination is that the assay plot of absorbance at 595 nm, the peak wavelength of the CrEL-dye complex, versus the concentration of the surfactant is not linear. The present study shows that the nonlinearity is associated with a decrease in the free dye concentration and a reduction in complex formation by increasing the CrEL concentration. By measurement of the ratio of absorbances at the maxima of the red (450 nm) and blue charge forms (595 nm) of Coomassie brilliant blue G-250, a full-scale linear relationship can be obtained over the entire range studied (0.500 to 10.0 microliter/mL). Validation data revealed that transformation of the detection procedure exhibits significantly improved specificity, accuracy(</= 6.33% relative error), and precision (< 10.0%) compared to our previous assay. The modified method was successfully applied to the measurement of CrEL in plasma of 11 cancer patients treated with a 1-h infusion of paclitaxel.

Clinical phase I study with one-hour paclitaxel infusion

BACKGROUND

Paclitaxel (PAC) is one of the major anti-cancer drugs, effective in different tumors. Studies with 24-hour infusion with 135 mg/m2 and a three-hour infusion with 175 mg/m2 showed a significant schedule-dependent toxicity. We evaluated a one-hour infusion schedule within a phase I study to determine the dose limiting toxicity (DLT), the maximum tolerated dose (MTD), and the anti-cancer efficacy.

PATIENTS AND METHODS

Patients with advanced malignant tumors were treated within cohorts by one-hour infusional paclitaxel starting with 150 mg/m2 and stepwise escalation with 25 mg/m2 increments. Therapy was repeated in three-week intervals. Cycles were repeated until progression. Toxicity was closely monitored, anti-cancer efficacy was only evaluated in those patients who received at minimum two treatment cycles.

RESULTS

Thirty-four patients entered the study (11 NSCLC, five SCLC, seven ovarian cancer, one cervix cancer, nine MBC, one HN cancer). The MTD was PAC 250 mg/m2. The DLT was central and peripheral neuropathy (WHO grade 3). Other significant toxicities were fatigue, myalgia/arthralgia and paraesthesia. No significant myelotoxicity was observed. Totally twentyone patients were evaluable for response. A partial response was observed in five (24%) patients (two NSCLC, two ovarian cancer, one head and neck cancer). Three (14%) patients had stable disease and in 13 (62%) patients progressive disease was observed.

CONCLUSIONS

Paclitaxel 225 mg/m2 on day 1 administered as one-hour infusion and repeated every three weeks can be given safely, featured no relevant myelotoxicity, and is the recommended dose for phase II studies.

Phase I study of paclitaxel administered as a 1-hour infusion: toxicity and pharmacokinetics

Paclitaxel (Taxol; Bristol-Myers Squibb Company, Princeton, NJ) is one of the most important new drugs used in the treatment of solid tumors. Use of paclitaxel, however, is associated with some toxicity. The main adverse side effects include myelotoxicity, neurotoxicity, hypersensitivity reactions, and asthenia. Toxicity seems to be schedule dependent. Currently, paclitaxel is routinely administered via 3- or 24-hour infusions. This study was performed to evaluate the toxicity and pharmacokinetics of a 1-hour infusion. Thirty-four patients with incurable solid tumors were included. Dose levels were escalated from 150 to 250 mg/m2. Thirty-four patients received a total of 105 courses of paclitaxel. The dose-limiting toxicity was World Health Organization grade 3 neuropathy at a dose of 250 mg/m2 in two of three patients. Two patients were not evaluable for dose-limiting toxicity because treatment was stopped after fewer than three courses due to disease progression. Neither had experienced a dose-limiting toxicity. Other toxicities were World Health Organization grade 1/2 neutropenia, asthenia, myalgia, arthralgia, and grade 1 hypersensitivity. Twenty-one patients were evaluable for preliminary anticancer efficacy. A partial response was observed in five patients (24%), stable disease in three (14%), and progressive disease in 13 (62%). The maximum tolerated dose was established at 250 mg/m2. A dose of 225 mg/m2 is recommended for further phase II trials. There was considerable interindividual and some intraindividual variability in pharmacokinetic parameters. Paclitaxel pharmacokinetics were linear up to 225 mg/m2, while a slightly overproportional increase in the peak plasma concentration and the area under the concentration-time curve was observed at 250 mg/m2, suggesting that paclitaxel's pharmacokinetic characteristics may be nonlinear at higher doses.

[A new measuring device for computer-assisted imaging of the form and flexibility of the spine]

Our aim is to present a new method to examine spinal mobility and spine shape excluding torsional scoliosis. In comparison to measuring devices of the spine used so far, this noninvasive and easy to use method documents altered patterns of intervertebral mobility of the lumbar and thoracic spine. This may lead to a broader application of the triflexometer as a diagnostic tool for orthopedic and rheumatologic diseases that can decrease the frequency of X-ray exposure if used in combination with radiographs. In the present investigation the triflexometer demonstrates a good reproducibility of the triflexometer-based measurements. These findings support the ability of the triflexometer to depict disease courses of spinal disorders as well as the effect of therapy and rehabilitation.