Abstract CT035: A phase Ib study of miransertib (ARQ 092) in combination with anastrozole in patients with PIK3CA or AKT1-mutant ER+ endometrial or ovarian cancer

Background: Activating PI3K pathway mutations are common in endometrial and a subset of non-serous ovarian cancers and are frequently found in tumors that co-express the estrogen receptor (ER). We evaluated the safety and preliminary efficacy of miransertib, a potent pan-AKT inhibitor, in combination with the aromatase inhibitor (AI) anastrozole in pts with PIK3CA and AKT1-mutant ER+ endometrial and ovarian cancer.

Methods: Eligible patients included endometrial and ovarian cancer patients (pts) with ER+ by immunohistochemistry and a PIK3CA or AKT1 mutation documented by local sequencing assays. There was no limit to prior lines of therapy including prior AIs. Miransertib dose was escalated according to a 3+3 design. TEAEs were assessed per CTCAE v. 4.03. Tumor responses were evaluated per RECIST 1.1.

Results: A total of 11 pts (8 endometrial, 3 ovarian) were enrolled (median age 60 years). Pts were treated at one of 2 miransertib doses: 200 mg QD, 5 days on/9 days off (n=6) or 150 mg QD, 5 days on/9 days off (n=5). All pts received anastrozole 1 mg QD administered continuously. 2 DLTs observed (both at the miransertib 200mg): grade 3 ALT increase and grade 3 rash. Across all cycles, a total of 4 pts experienced a Grade 3 miransertib-related AE including rash (n=2), ALT increase (n=1), and hyperglycemia (n=1). There were no grade 4/5 miransertib-related AEs. Miransertib 150mg was selected as the recommended dose. 4 pts achieved a response (1 confirmed CR, 3 unconfirmed PRs - 1 pending confirmation, see Table). All responses (confirmed and unconfirmed) were in endometrial cancer (4/8 pts). In responding pts, mutations involved PIK3CA (n=3) and AKT1 (n=1). 50% (2/4) responding pts had received ≥1 prior line of endocrine therapy. Responses were ongoing in 2 of 4 patients, with the longest continuing at 60 weeks.

Conclusions: The combination of miransertib and anastrozole demonstrated a manageable safety profile and preliminary efficacy. Responses were observed in endometrial pts with PIK3CA or AKT1 mutation and those who had received prior endocrine therapy. Enrollment at the recommended combination dose is ongoing and updated response data will be presented.

*pt had PD at 24 weeks but continues for ongoing benefit at 56 weeks.Pt IDPrimary SiteHistologyGradeMutationLines of prior therapyBest RECIST response (confirmed)Duration on treatment (weeks)1EndometrialMixed endometriod/serous1PIK3CA H1047R3CR60+2EndometrialEndometriod2PIK3CA H1047R4uPR24*3EndometrialEndometriod1PIK3CA H1047R4SD124EndometrialSerous3PIK3CA R115L1PD85EndometrialEndometriod1PIK3CA E545K and H1047L2NE46OvarySerous3PIK3CA H1047R5PD77OvaryEndometriod1PIK3CA T1025S2PD88EndometrialSerous3PIK3CA N345K2uPR169OvarySerous3PIK3CA E542K5PD510EndometrialSerous3AKT1 E17K1uPR**12+11EndometrialSerous3PIK3CA C901F3PD9*pt had PD at 24 weeks but continues for ongoing benefit at 56 weeks**pending confirmation

Citation Format: David Hyman, Michael Bonafede, Roisin O'Cearbhaill, Rachel Grisham, Dmitriy Zamarin, William Tew, Carol Aghajanian, Karen Cadoo, Claire Friedman, Ron E. Savage, Feng Chai, Brian Schwartz, Vicky Makker. A phase Ib study of miransertib (ARQ 092) in combination with anastrozole in patients with PIK3CA or AKT1-mutant ER+ endometrial or ovarian cancer [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2018; 2018 Apr 14-18; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2018;78(13 Suppl):Abstract nr CT035.

Trends in overall survival and costs of multiple myeloma, 2000-2014

Little real-world evidence is available to describe the recent trends in treatment costs and outcomes for patients with multiple myeloma (MM). Using the Truven Health MarketScan Research Databases linked with social security administration death records, this study found that the percentage of MM patients using novel therapy continuously increased from 8.7% in 2000 to 61.3% in 2014. Compared with MM patients diagnosed in earlier years, those diagnosed after 2010 had higher rates of novel therapy use and better survival outcomes; patients diagnosed in 2012 were 1.25 times more likely to survive 2 years than those diagnosed in 2006. MM patients showed improved survival over the study period, with the 2-year survival gap between MM patients and matched controls decreasing at a rate of 3% per year. Total costs among MM patients have increased in all healthcare services over the years; however, the relative contribution of drug costs has remained fairly stable since 2009 despite new novel therapies coming to market. Findings from this study corroborate clinical data, suggesting a paradigm shift in MM treatment over the past decade that is associated with substantial survival gains. Future studies should focus on the impact on specific novel agents on patients' outcomes.

Predicting imminent risk for fracture in patients aged 50 or older with osteoporosis using US claims data

Patient characteristics contributing to imminent risk for fracture, defined as risk of near-term fracture within the next 12 to 24 months, have not been well defined. In patients without recent fracture, we identified factors predicting imminent risk for vertebral/nonvertebral fracture, including falls, age, comorbidities, and other potential fall risk factors.

PURPOSE

Several factors contribute to long-term fracture risk in patients with osteoporosis, including age, bone mineral density, and fracture history. Some patients may be at imminent risk for fracture, defined here as a risk of near-term fracture within 12-24 months. Many patient characteristics contributing to imminent risk for fracture have not been well defined. This case-control study used US commercial and Medicare supplemental insured data for women and men without recent fracture to identify factors associated with imminent risk for fracture.

METHODS

Patients included were aged ≥50 with osteoporosis, had a vertebral or nonvertebral fracture claim (index date; fracture group) or no fracture claim (control group) from January 1, 2006, to September 30, 2012, continuously enrolled and without fracture in the 24 months before index. Potential risk factors during the period before fracture were assessed.

RESULTS

Using data from 12 months before fracture, factors significantly associated with imminent risk for fracture were previous falls, older age, poorer health status, specific comorbidities (psychosis, Alzheimer's disease, central nervous system disease), and other fall risk factors (wheelchair use, psychoactive medication use, mobility impairment). Similar findings were observed with data from 24 months before fracture.

CONCLUSIONS

In patients with osteoporosis and no recent fracture, falls, older age, poorer health status, comorbidities, and other potential fall risk factors were predictive of imminent risk for fracture. Identification of factors associated with imminent risk for vertebral/nonvertebral fracture may help identify and risk stratify those patients most in need of immediate and appropriate treatment to decrease fracture risk.

Outcomes of Systemic Therapy for Patients with Metastatic Angiosarcoma

BACKGROUND

Angiosarcomas (AS) are rare tumors of vascular origin with a variable behavior and overall poor prognosis. We sought to assess the outcomes of patients treated for metastatic disease.

METHODS

We performed a retrospective analysis of 119 patients treated for metastatic AS. Outcomes and efficacy measurements of the first and subsequent lines of treatment were analyzed.

RESULTS

Median age was 61 years, and the most frequent primary sites were chest wall/breast (31%), viscera (22%) and head/neck (20%). Seventy-three (61%) and 46 (39%) patients received ≥ 2 and ≥ 3 lines of therapy, respectively. The most commonly used agents included taxanes and anthracyclines. Median overall survival was 12.1 months. Median times to tumor progression were 3.5 months for first line, 3.7 months for second line and 2.7 months for third line. Among 48 patients evaluable per RECIST, the overall response rate to first line was 30% and <10% in subsequent lines. Doxorubicin, liposomal doxorubicin and taxanes resulted in similar response rates and survival, and there was no apparent benefit for combination chemotherapy.

CONCLUSION

Despite reasonable response rates in the first-line setting, benefit from systemic therapy is short-lived in metastatic AS, and outcomes are poor. Doxorubicin, liposomal doxorubicin and taxanes are reasonable and appropriate choices for monotherapy.

Development of a refractory gastro-oesophageal reflux score using an administrative claims database

BACKGROUND

Approximately one-third of gastro-oesophageal reflux disease (GERD) patients demonstrate refractory symptoms following treatment with proton pump inhibitor (PPI) therapy.

AIM

To develop a refractory GERD score that can be applied to predict patients' healthcare utilisation.

METHODS

We enrolled adults (≥18 years) with a diagnosis of GERD. Refractory GERD was evaluated on an 8-point scale where 1 point was given for each of the following criteria: doubling, addition, or switching of GERD medication dose, receipt of a GERD-related endoscopic procedure or surgery, or ≥3 GERD-related outpatient visits. Refractory GERD was defined as the presence of two or more points.

RESULTS

A total of 135,139 GERD patients (44% male) were analysed with a mean (±s.d.) age of 52.9 ± 15 years. The mean overall refractory GERD score was 1.12 ± 1.2 (range 0-8 on an 8-point scale); 31% of patients had refractory GERD with a mean score of 2.56 ± 0.82. Among patients with refractory GERD, 31% doubled their GERD medication, 28% added a new GERD medication, 60% switched GERD medications, 54% had a GERD-related procedure and 1% had a GERD-related surgery. Patients with refractory GERD were more likely to be female (59% vs. 55%, P < 0.001) and had a higher co-morbidity score (0.78 vs. 0.56, P < 0.001). The overall mean costs for refractory patients during the study period were significantly higher compared with treatment-responsive patients ($18,088 ± $36,220 vs. $11,044 ± $22,955, P < 0.001).

CONCLUSIONS

Refractory GERD was present in approximately one-third of the GERD patients. We created a GERD refractory score that could define need for increased anti-reflux therapy and predict higher healthcare resource utilisation.

The wheat and barley vernalization gene VRN3 is an orthologue of FT

Winter wheat and barley varieties require an extended exposure to low temperatures to accelerate flowering (vernalization), whereas spring varieties do not have this requirement. In this study, we show that in these species, the vernalization gene VRN3 is linked completely to a gene similar to Arabidopsis FLOWERING LOCUS T (FT). FT induction in the leaves results in a transmissible signal that promotes flowering. Transcript levels of the barley and wheat orthologues, designated as HvFT and TaFT, respectively, are significantly higher in plants homozygous for the dominant Vrn3 alleles (early flowering) than in plants homozygous for the recessive vrn3 alleles (late flowering). In wheat, the dominant Vrn3 allele is associated with the insertion of a retroelement in the TaFT promoter, whereas in barley, mutations in the HvFT first intron differentiate plants with dominant and recessive VRN3 alleles. Winter wheat plants transformed with the TaFT allele carrying the promoter retroelement insertion flowered significantly earlier than nontransgenic plants, supporting the identity between TaFT and VRN-B3. Statistical analyses of flowering times confirmed the presence of significant interactions between vernalization and FT allelic classes in both wheat and barley (P < 0.0001). These interactions were supported further by the observed up-regulation of HvFT transcript levels by vernalization in barley winter plants (P = 0.002). These results confirmed that the wheat and barley FT genes are responsible for natural allelic variation in vernalization requirement, providing additional sources of adaptive diversity to these economically important crops.

CD11b expression identifies CD8+CD28+ T lymphocytes with phenotype and function of both naive/memory and effector cells

A previously unreported CD8(+)CD28(+)CD11b(+) T cell subset occurs in healthy individuals and expands in patients suffering from primary viral infections. In functional terms, these cells share the features of naive/memory CD8(+)CD28(+)CD11b(-) and terminally differentiated effector CD8(+)CD28(-)CD11b(+) subpopulations. Like CD28(-) cells, CD28(+)CD11b(+) lymphocytes have the ability to produce IFN-gamma, to express perforin granules in vivo, and to exert a potent cytolytic activity. Moreover, these cells can respond to chemotactic stimuli and can efficiently cross the endothelial barrier. In contrast, like their CD11b(-) counterpart, they still produce IL-2 and retain the ability to proliferate following mitogenic stimuli. The same CD28(+)CD11b(+) subpopulation detected in vivo could be generated by culturing naive CD28(+)CD11b(-) cells in the presence of mitogenic stimuli following the acquisition of a CD45RO(+) memory phenotype. Considering both phenotypic and functional properties, we argue that this subset may therefore constitute an intermediate phenotype in the process of CD8(+) T cell differentiation and that the CD11b marker expression can distinguish between memory- and effector-type T cells in the human CD8(+)CD28(+) T cell subset.

High-level expression of chromosomally encoded SHV-1 beta-lactamase and an outer membrane protein change confer resistance to ceftazidime and piperacillin-tazobactam in a clinical isolate of Klebsiella pneumoniae

We describe Klebsiella pneumoniae 15571, a clinical isolate resistant to ceftazidime MIC = 32 microg/ml) and piperacillin-tazobactam (MICs = 1,024 and 128 microg/ml). K. pneumoniae 15571 expresses a single beta-lactamase with a pI of 7.6. However, when cloned in a high-copy-number vector in Escherichia coli, this bla(SHV-1) gene did not confer resistance to ceftazidime, a spectrum consistent with the nucleotide sequence, which was nearly identical to those of previously described bla(SHV-1) genes. Outer membrane protein (OMP) analysis of K. pneumoniae 15571 revealed a decrease in the quantity of a minor 45-kDa OMP in comparison to that in K. pneumoniae 44NR, a low-level ampicillin-resistant strain that also expresses a chromosomally determined bla(SHV-1). Crude beta-lactamase enzyme extracts from K. pneumoniae 15571 produced roughly 200-fold more beta-lactamase activity than K. pneumoniae 44NR. Northern hybridization analysis revealed that this difference was explainable by quantifiable differences in transcription of the bla(SHV-1) gene in the two strains. Primer extension analysis of bla(SHV-1) mRNA from K. pneumoniae 15571 and 44NR indicated that the transcriptional start sites were identical in the two strains. DNA sequencing of the promoter regions upstream of the of bla(SHV-1) open reading frames in the two K. pneumoniae strains revealed an A-->C change in the second position of the -10 region in K. pneumoniae 44NR compared to that in 15571. Site-directed mutagenesis of the cloned K. pneumoniae 15571 bla(SHV-1), in which the A in the second position of the 15571 -10 region was changed to a C, resulted in a substantial lowering of the MIC of ampicillin. When the levels of beta-lactamase enzyme expression in E. coli were compared, the bla(SHV-1) downstream of the altered -10 region produced 17-fold less beta-lactamase enzyme. These results indicate that elevated levels of ceftazidime resistance can result from a combination of increased enzyme production and minor OMP changes and that levels of chromosomally encoded SHV-1 beta-lactamase production can vary substantially with a single-base-pair change in promoter sequence.