Challenges in initiating and conducting personalized cancer therapy trials: perspectives from WINTHER, a Worldwide Innovative Network (WIN) Consortium trial

Advances in 'omics' technology and targeted therapeutic molecules are together driving the incorporation of molecular-based diagnostics into the care of patients with cancer. There is an urgent need to assess the efficacy of therapy determined by molecular matching of patients with particular targeted therapies. WINTHER is a clinical trial that uses cutting edge genomic and transcriptomic assays to guide treatment decisions. Through the lens of this ambitious multinational trial (five countries, six sites) coordinated by the Worldwide Innovative Networking Consortium for personalized cancer therapy, we discovered key challenges in initiation and conduct of a prospective, omically driven study. To date, the time from study concept to activation has varied between 19 months at Gustave Roussy Cancer Campus in France to 30 months at the Segal Cancer Center, McGill University (Canada). It took 3+ years to be able to activate US sites due to national regulatory hurdles. Access to medications proposed by the molecular analysis remains a major challenge, since their availability through active clinical trials is highly variable over time within sites and across the network. Rules regarding the off-label use of drugs, or drugs not yet approved at all in some countries, pose a further challenge, and many biopharmaceutical companies lack a simple internal mechanism to supply the drugs even if they wish to do so. These various obstacles should be addressed to test and then implement precision medicine in cancer.

Phase I study of pazopanib and vorinostat: a therapeutic approach for inhibiting mutant p53-mediated angiogenesis and facilitating mutant p53 degradation

BACKGROUND

We carried out a phase I trial of the vascular endothelial growth factor inhibitor pazopanib and the histone deacetylase inhibitor vorinostat to determine the safety and efficacy. Because these agents are known to target factors activated by TP53 mutation and facilitate mutant p53 degradation, a subgroup analysis may be interesting in patients with TP53 mutant malignancies.

PATIENTS AND METHODS

Patients with advanced solid tumors (n = 78) were enrolled following a 3 + 3 design, with dose expansion for those with responsive tumors. Hotspot TP53 mutations were tested when tumor specimens were available.

RESULTS

Adverse events of ≥grade 3 included thrombocytopenia, neutropenia, fatigue, hypertension, diarrhea and vomiting. Overall, the treatment produced stable disease for at least 6 months or partial response (SD ≥6 months/PR) in 19% of the patients, median progression-free survival (PFS) of 2.2 months, and median overall survival (OS) of 8.9 months. In patients with detected hotspot TP53 mutant advanced solid tumors (n = 11), the treatment led to a 45% rate of SD ≥6 months/PR (1 PR and 3 SD ≥6 months), median PFS of 3.5 months, and median OS of 12.7 months, compared favorably with the results for patients with undetected hotspot TP53 mutations (n = 25): 16% (1 PR and 3 SD ≥6 months, P = 0.096), 2.0 months (P = 0.042), and 7.4 months (P = 0.1), respectively.

CONCLUSION

The recommended phase II dosage was oral pazopanib at 600 mg daily plus oral vorinostat at 300 mg daily. The preliminary evidence supports further evaluation of the combination in cancer patients with mutated TP53, especially in those with metastatic sarcoma or metastatic colorectal cancer.

CLINICAL TRIAL REGISTRATION

www.clinicaltrials.gov, NCT01339871.

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.

Melanoma patients in a phase I clinic: molecular aberrations, targeted therapy and outcomes

BACKGROUND

The purpose of the study was to assess the outcome of patients with advanced melanoma treated with matched molecularly targeted therapy.

PATIENTS AND METHODS

We reviewed 160 consecutive patients with metastatic melanoma treated in the phase I program (N = 35 protocols). Treatment was considered to be 'matched' (N = 84) if at least one drug in the regimen was known to inhibit the functional activity of at least one of the patient's mutations.

RESULTS

Of 160 patients, 134 (83.7%) had adequate tissue for molecular analysis; 69% (110 of 160) had ≥1 mutation: 61.2% (82 of 134), BRAF; 20.7% (23 of 111), NRAS; 2.6% (2 of 77), KIT; 2.3% (1 of 44), KRAS; 20% (1 of 5), GNAQ; 11.1% (1 of 9), P53 and 2.6% (1 of 39), coexisting mutations in BRAF and PIK3CA. Eighty-four patients (52.4%) were treated with matched-targeted agents, most of whom had BRAF mutations (N = 74). Twenty-six percent of patients (41 of 160) achieved a complete or partial remission (CR/PR) [40% (34 of 84)) on a matched phase I protocol versus 9.2% (7 of 76) for those on a non-matched study (P ≤ 0.0001)]. The median progression-free survival (PFS) (95% CI) was longer for patients treated on a matched phase I trial than on their prior first standard treatment [5.27 (4.10, 6.44) versus 3.10 (1.92, 4.28) months, P = 0.023], but not on non-matched phase I treatment. Multivariable analysis showed that matched therapy was an independent predictor of higher CR/PR rates, prolonged PFS and survival.

CONCLUSIONS

For melanoma patients, especially those with BRAF mutations, administering molecularly matched agents can be associated with better outcomes, including longer PFS compared with their first-line systemic therapy.

Abstract P5-20-09: Tumor mutational analysis and therapy outcomes for patients (pts) with metastatic/unresectable locally advanced myoepithelial/metaplastic breast cancer treated with PI3K targeted therapy

Background: Metaplastic breast cancers are considered a chemorefractory subset of triple negative breast cancers. Molecular profiling has demonstrated that metaplastic tumors are enriched for epithelial-to-mesenchymal transition (EMT), frequently express myoepithelial differentiation, make up a component of the ‘claudin-low’ subtype, and harbor relatively high rates of mutations/activation of the PI3kinase pathway (Hennessy, Cancer Research, 2009; Prat, Breast Cancer Res, 2010).

Methods: Data from pts with myoepithelial/metaplastic breast cancer treated within the Center for Targeted Therapy using regimens with known inhibitors of the PI3K pathway were evaluated to determine response to therapy. Mutational analyses were performed in archived tumor samples when available.

Results: 23 pts have been treated using 6 different therapy regimens and one pt was treated on two separate clinical trials for a total of 24 analyzable outcomes. Patients were treated with liposomal doxorubicin, bevacizumab and the mTOR inhibitor, temsirolimus (DAT, n=17); liposomal doxorubicin and temsirolimus (DT, n=1); paclitaxel, bevacizumab and temsirolimus (TAT, n=3); paclitaxel and temsirolimus (TT, n=1), paclitaxel in combination with an experimental PI3K inhibitor (TEx, n=1), or temsirolimus alone (tem, n=1). Response was measured every two cycles using RECIST criteria. Most pts had received prior chemotherapy, median of 2 prior regimens (range 0–7). Three patients were not evaluated for response, one who died of pneumonia during cycle 2 (DAT) and two who have not yet completed 2 cycles of therapy (DAT, TEx). Response rate (CR+PR) was 35% (CR = 2, PR=4, SD≥6 months=2, SD<6 months=2, PD/death=7) with the anthracycline based regimens, DAT and DT; whereas, stable disease was the best response seen thus far with the paclitaxel based regimens or temsirolimus alone: TAT (SD<6months=2, PD=1), TT (SD<6months=1), tem (SD<6months=1). 8 of 9 tumors tested (89%) were found to have mutations that would lead to activation of the PI3K pathway: PIK3CA=5 (62%), PTEN=2 (25%) and NF2=1(13%). The two patients with CR from DAT had mutations in NF2 and PIK3CA, respectively. Both patients remain in CR (2+ years and 1+ year respectively) after discontinuing protocol therapy, and both continue maintenance everolimus.

Conclusion: Activating mutations in the PI3K pathway are common in metaplastic breast cancers, a tumor subtype that shares molecular features with claudin-low and mesenchymal/mesenchymal-stem cell like triple negative breast cancers. DAT has demonstrated activity in myoepithelial/metaplastic breast cancer including two durable CRs to therapy. This regimen should be explored in larger, randomized trials to test superiority to chemotherapy alone.

Citation Information: Cancer Res 2012;72(24 Suppl):Abstract nr P5-20-09.

Clinical outcomes of patients with breast cancer in a phase I clinic: The M. D. Anderson Cancer Center experience

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Background: Patients with metastatic breast cancer refractory to standard therapy are eligible for phase I trials. We assessed prognostic factors and clinical outcomes for patients with breast cancer in a phase I clinic focused on targeted agents. Methods: We reviewed the medical records of sequential patients with metastatic breast cancer who presented to our phase I clinic from September 2004 to May 2008. We assessed the relationship between overall survival and patients’ demographic and clinical characteristics using both univariate and multivariate (Cox proportional hazard model) analyses. Results: Ninety-two patients were identified with median age of 53 years (range 28 to 83 years). The median number of prior therapies was 5 (range 1 to 16). The median follow-up of surviving patients is 7.4 months. The median overall survival is 6.7 (95% CI: 5.2, 9.7) months. In univariate analysis, factors predicting shorter survival were elevated Ca-125 (p = 0.001) (Ca27.29 was not significant), albumin < 3.5 g/dL (p = 0.002), worsening ECOG performance status (p = 0.004), absolute neutrophil count < 7.3 x 109/L (p = 0.004), ≥ 10 prior treatment regimens (p = 0.008), ≥ 5 prior chemotherapy-only regimens (p = 0.008), body mass index (BMI) < 25 (p = 0.018), and elevated platelet counts (p = 0.007). In multivariate analysis, independent factors predicting shorter survival were ≥10 prior treatments (vs. <10 prior treatments) (HR = 3.27; 95% CI 1.37, 7.81; p = 0.0077), ECOG performance status 2–3 (vs. 0–1) (HR = 2.92; 95% CI 1.28, 6.66; p = 0.01), and albumin < 3.5 g/dL (vs. > 3.5g/dL) (hazard ratio [HR] = 2.88; 95% CI; 1.41, 5.89; p = 0.004). Of 78 patients treated on a first phase I trial, 14 (18%) demonstrated stable disease (SD), with a median duration of 18 weeks (range 10–25). Of those 19 patients treated on a second phase I trial, 6 (32%) had SD with a median duration of 12 weeks (range 8–17). Two of 4 (50%) patients treated on a third phase I trial had SD with a median duration of 20 weeks (range 16–24). Conclusions: Patients with metastatic breast cancer referred for our phase I studies had a median survival of 6.6 months. In this preliminary analysis, independent factors predicting shorter survival were ≥ 10 prior treatments, worsening ECOG performance status and low albumin levels.

No significant financial relationships to disclose.

The combination of oxaliplatin, fludarabine (FLU), cytarabine (Ara-c), and rituximab (R) (OFAR) in patients with Richter’s Transformation and FLU-refractory CLL

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Background: Patients with (FLU-ref) CLL and Richter’s transformation (RT) have a very poor prognosis. Oxaliplatin (OX), a platinum analog with a 1,2-diaminocyclohexamine carrier ligand, has a different activity and side effect profile from cisplatin. OX covalently binds DNA, inducing DNA intra- and inter-strand cross-links. FLU and Ara-c act synergistically to inhibit excision-repair of DNA cross-links, thereby providing the rationale for combining OX, FLU, Ara-c, and R (OFAR). Methods: The phase I portion of a phase I/II study of the OFAR regimen had increasing doses of OX. The OFAR regimen consists of OX 17.5, 20, or 25mg/m2, d1–4; fludarabine 30mg/m2, d2,3; Ara-c 1gm/m2, d2,3; and rituximab 375mg/m2, d3. Courses were given every 4 wks; patients received Neulasta 6mg each course and prophylaxis for tumor lysis, DNA virus’, and PCP. Results: 19 patients enrolled in phase I; 1 received no treatment, 8 had RT, and 10 had FLU-ref CLL. Patients received OX 17.5mg/m2 (3), 20mg/m2 (8), or 25mg/m2 (7). Patients receiving at least 1 course were evaluable for toxicity and could receive up to 6 courses. There were no dose-limiting toxicities, defined as any ≥ G3, non-hematologic, treatment-related toxicity. The major toxicity was hematologic and appeared OX-dose dependent. Neutropenia (G3–4) was experienced by 1/3, 6/8, and 7/7 patients treated at 17.5, 20, and 25mg/m2 OX levels, respectively. Thrombocytopenia (G3–4) was experienced by 2/3, 8/8, and 7/7 of patients treated at 17.5, 20, and 25mg/m2m OX levels, respectively. There were no treatment-related deaths. Five patients continue treatment on the phase I portion, and results will be evaluable, with 3 responders, including 2 complete, in the 7 evaluable patients with RT. Among the 10 FLU-ref patients, there are 5 PRs; treatment continues for 3 of them. Pharmacodynamic analyses demonstrate enhanced killing by OX in the presence of FLU and Ara-c. Conclusions: The OFAR regimen is safe and active for treating patients with RT and FLU-ref CLL. This trial continues to accrue patients to confirm efficacy.

No significant financial relationships to disclose.

Severe aplastic anaemia relapsing during a pregnancy; spontaneous remission following termination

The case of a 29-year-old woman with aplastic anaemia in remission who relapsed during pregnancy is reported here. Following successful Caesarean delivery, spontaneous remission was obtained and the patient remains well thereafter. Pathogenetic and therapeutic aspects of this rare complication of pregnancy are discussed.

Detection of "PNH red cell" populations in hematological disorders using the Sephacryl Gel Test micro typing system

Paroxysmal nocturnal hemoglobinuria (PNH) is an acquired clonal disorder characterised by an unusual sensitivity of abnormal red cell population(s) to complement lysis, due to a complete or incomplete defect of various surface molecules, including CD55 and CD59. PNH has been associated with various hematological disorders. Using a newly introduced method, the Sephacryl gel test microtyping system, we investigated the presence of CD55 or CD59 defective red cell populations in several hematological disorders. It was also found that a large proportion of such patients possess CD55 deficient populations, while a smaller but still significant proportion possess CD59 deficient populations. Defective red cell populations were detected in normal subjects as well. These findings need further investigation. Nevertheless the Sephacryl Gel Test microtyping system although non specific, seems to be useful in screening for the PNH and/or "PNH-like" red cell defect in several hematological disorders.