First-in-human study of pbi-05204, an oleander-derived inhibitor of akt, fgf-2, nf-κΒ and p70s6k, in patients with advanced solid tumors.

BACKGROUND: PBI-05204, a Nerium oleander extract (NOE) containing the cardiac glycoside oleandrin, inhibits the α-3 subunit of Na-K ATPase, as well as FGF-2 export, Akt and p70S6K, hence attenuating mTOR activity. This first-in-human study determined the safety, pharmacokinetics (PK) and pharmacodynamics (PD) of PBI-05204 in patients with advanced cancer. Methods Forty-six patients received PBI-05204 by mouth for 21 of 28 days (3 + 3 trial design). Dose was escalated 100% using an accelerated titration design until grade 2 toxicity was observed. Plasma PK and mTOR effector (p70S6K and pS6) protein expressions were evaluated. Results Dose-limiting toxicities (grade 3 proteinuria, fatigue) were observed at dose level 8 (0.3383 mg/kg/day). Common possible drug-related adverse were fatigue (26 patients, 56.5%), nausea (19 patients, 41.3%) and diarrhea (15 patients, 32.6 %). Electrocardiogram monitoring revealed grade 1 atrioventricular block (N = 10 patients) and grade 2 supraventricular tachycardia (N = 1). The MTD was DL7 (0.2255 mg/kg) where no toxicity of grade ≥ 3 was observed in seven patients treated. Seven patients (15%) had stable disease > 4 months. Mean peak oleandrin concentrations up to 2 ng/mL were achieved, with area under the curves 6.6 to 25.5 µg/L*hr and a half-life range of 5-13 h. There was an average 10% and 35% reduction in the phosphorylation of Akt and pS6 in PBMC samples in 36 and 32 patients, respectively, tested between predose and 21 days of treatment. Conclusions PBI-05204 was well tolerated in heavily pretreated patients with advanced solid tumors. The recommended Phase II dose is 0.2255 mg/kg/day.

Tumor marker and measurement fluctuations may not reflect treatment efficacy in patients with medullary thyroid carcinoma on long-term RET inhibitor therapy.

BACKGROUND: RET kinase inhibitors have significant activity in patients with medullary thyroid carcinoma (MTC). PATIENTS AND METHODS: We retrospectively reviewed the electronic medical record for patterns of calcitonin, carcinoembryonic antigen (CEA) and tumor measurement responses in consecutive patients with MTC who received treatment with a RET inhibitor for at least 6 months. RESULTS: Twenty-six patients who received RET kinase inhibitors for at least 6 months were included. All patients experienced an initial decline in calcitonin; 20 (77%) demonstrated later fluctuations in calcitonin, which spiked above baseline levels in 9 individuals (35%). Twenty of the 22 patients (91%) with elevated CEA experienced a decline with treatment, with 11 individuals (50%) later demonstrating transient fluctuations in CEA, including spikes above baseline in 7 patients (32%). Ten of the 26 patients (38%) also demonstrated short-lived fluctuations in RECIST measurements, including changes of over 20% from nadir values. Vacillations in calcitonin, CEA and measurements often occurred repeatedly in individual patients and did not regularly correlate with each other. CONCLUSIONS: Repeated transient fluctuations in tumor markers and measurements are a characteristic of patients with MTC receiving treatment with RET inhibitors, and such short-term vacillations may not reflect responsiveness over the long term. CLINICAL TRIALS INCLUDED: NCT00215605; NCT00244972; NCT00121680; NCT00495872.

Electrocardiograms (ECGs) in phase I anticancer drug development: the MD Anderson Cancer Center experience with 8518 ECGs.

BACKGROUND: Cardiac sequelae from oncologic drugs are important in early cancer drug development. Prolongation of the corrected QT interval (QTc) by noncardiac drugs is the most common cause of drug development delays, nonapprovals and postmarketing withdrawals by the US Food and Drug Administration. PATIENTS AND METHODS: We analyzed 8518 electrocardiograms (ECGs) in 525 consecutive cancer patients enrolled in 22 industry-sponsored phase I clinical trials, starting 1 January 2006. RESULTS: Seventy-four patients [14%, 95% confidence interval (CI) 11% to 17%] with normal QTc at baseline had QTc intervals above upper limit of normal after treatment initiation; 33 (6%, 95% CI 4% to 9%) had prolonged QTc intervals at baseline, and only one (3%, 95% CI 0% to 16%) worsened after dosing. Seven of 33 patients (21%, 95% CI 9% to 39%) with prolonged baseline QTc had normalization of QTc intervals after dosing. All QTc prolongations were clinically insignificant; study drugs were continued uneventfully. Two of 525 patients (0.4%, 95% CI 0% to 1%) experienced cardiac serious adverse events (myocardial infarction possibly related to drug and unstable atrial flutter related to metastatic disease). Both cardiac events were detected by clinical assessment, not surveillance ECGs. CONCLUSION: Frequent ECG monitoring provided no clinically significant information in 525 patients in early phase trials.

Reduced-intensity conditioning for allogeneic hematopoietic stem cell transplantation with fludarabine and melphalan is associated with durable disease control in myelodysplastic syndrome.

We retrospectively evaluated the outcome of reduced-intensity conditioning (RIC) followed by allogeneic hematopoietic stem cell transplantation (HCT) in 43 patients with myelodysplastic syndrome (MDS) or AML arising from MDS. All patients received fludarabine plus melphalan followed by an allogeneic HCT from an HLA-identical sibling (SIB: n=19) or unrelated donor (MUD: n=24). Median age was 58 years (range: 30-71). Diagnoses at transplantation were RA (n=8), RARS (n=1), RAEB (n=13), RAEB-T (n=6), or AML arising from MDS (n=15). Of 28 patients with MDS, two patients had low, 10 had intermediate-1, nine had intermediate-2 and seven had high-risk MDS by IPSS criteria. All patients initially engrafted with the median neutrophil recovery of 15 days (range: 9-27). The 2-year overall survival, disease-free survival, relapse and transplant-related mortality were 53.5% (CI 45.2-61.1), 51.2% (CI 43.3-58.5), 16.3% (CI 7.9-30.7) and 35.2% (26.4-45.7), respectively. Grade II-IV acute graft-versus-host disease occurred in 27 (63%) patients. There was no significant survival difference between SIB and MUD-HCT, but the relapse rate was higher among SIB donor recipients when compared to MUD (38.5 versus 7%, P=0.02). RIC with fludarabine plus melphalan was associated with durable disease control and acceptable toxicity in this high-risk cohort.