Late-stage Clinical Development Research Articles

The ABCs of the US Broad Spectrum Antimicrobials Program: Antibiotics, Biosecurity, and Congress.

Antibiotic resistance has been increasing at an alarming rate in the United States and globally for decades, but the problem has only recently gained broad attention at the highest levels of the US government. More and more patients are dying of infections that do not respond to antibiotics that are currently available. Meanwhile, the antibacterial product pipeline remains fragile in part because of a lack of commercial interest from pharmaceutical companies. The Biomedical Advanced Research and Development Authority (BARDA) Broad Spectrum Antimicrobials (BSA) program leads the US government's effort to bridge this gap by advancing new antibacterials through late stages of clinical development. Other commentators have described in detail BARDA's structure, process, and role in antibacterial development. This commentary offers a public policy perspective on the emerging politics of antibiotic resistance in the context of US biosecurity politics and medical countermeasure (MCM) development. It identifies promising developments and difficult challenges that together will ultimately determine whether BARDA can become a global leader for antibiotic development.

Pharmacology and Clinical Drug Candidates in Redox Medicine.

Significance: Oxidative stress is suggested to be a disease mechanism common to a wide range of disorders affecting human health. However, so far, the pharmacotherapeutic exploitation of this, for example, based on chemical scavenging of pro-oxidant molecules, has been unsuccessful. Recent Advances: An alternative emerging approach is to target the enzymatic sources of disease-relevant oxidative stress. Several such enzymes and isoforms have been identified and linked to different pathologies. For some targets, the respective pharmacology is quite advanced, that is, up to late-stage clinical development or even on the market; for others, drugs are already in clinical use, although not for indications based on oxidative stress, and repurposing seems to be a viable option. Critical Issues: For all other targets, reliable preclinical validation and drug ability are key factors for any translation into the clinic. In this study, specific pharmacological agents with optimal pharmacokinetic profiles are still lacking. Moreover, these enzymes also serve largely unknown physiological functions and their inhibition may lead to unwanted side effects. Future Directions: The current promising data based on new targets, drugs, and drug repurposing are mainly a result of academic efforts. With the availability of optimized compounds and coordinated efforts from academia and industry scientists, unambiguous validation and translation into proof-of-principle studies seem achievable in the very near future, possibly leading towards a new era of redox medicine. Antioxid. Redox Signal. 23, 1113–1129.

Oral Delivery of Therapeutic Proteins and Peptides: An Overview of Current Technologies and Recommendations for Bridging from Approved Intravenous or Subcutaneous Administration to Novel Oral Regimens.

Since the early 1980s, therapeutic proteins and peptides have become established as an important class of pharmaceuticals. Due to their low oral bioavailability, which results from pre-systemic degradation and poor gastrointestinal absorption, most therapeutic proteins and peptides are administered intravenously. While subcutaneous formulations of some therapeutic proteins and peptides have been shown to improve patient convenience and reduce medical resource utilization, oral administration is generally the preferred administration route. Some therapeutic proteins and peptides employing novel oral delivery technologies have reached late-stage clinical development. To develop a new oral formulation of a therapeutic protein or peptide currently marketed as an injectable product, technical, nonclinical, and clinical studies are required to demonstrate similar safety and efficacy compared with the existing administration route. Since there is little experience with oral therapeutic proteins and peptides, this review provides recommendations for bridging from an approved intravenous or subcutaneous regimen to novel oral administration of the same therapeutic protein or peptide, based on precedents from intravenous-to-subcutaneous bridging approaches for trastuzumab, rituximab, tocilizumab, and bortezomib. If the pharmacokinetic/pharmacodynamic relationship is well characterized, demonstration of comparability in prespecified pharmacokinetic parameters might form a basis for establishing similar efficacy and safety of the oral formulation vs. the reference product. Although oral administration of therapeutic proteins and peptides remains challenging, given recent progress with novel delivery technologies, intravenous/subcutaneous-to-oral nonclinical and clinical bridging programs may soon be utilized to support approval of new oral formulations.

Vaccination Against Dengue: Challenges and Current Developments.

Dengue is a growing threat worldwide, and the development of a vaccine is a public health priority. The completion of the active phase of two pivotal efficacy studies conducted in Asia and Latin America by Sanofi Pasteur has constituted an important step. Several other approaches are under development, and whichever technology is used, vaccine developers face several challenges linked to the particular nature and etiology of dengue disease. We start our review by defining questions and potential issues linked to dengue pathology and presenting the main types of vaccine approaches that have explored these questions; some of these candidates are in a late stage of clinical development. In the second part of the review, we focus on the Sanofi Pasteur dengue vaccine candidate, describing the steps from research to phase III efficacy studies. Finally, we discuss what could be the next steps, before and after vaccine introduction, to ensure that the vaccine will provide the best benefit with an acceptable safety profile to the identified target populations.

In vitro pharmacological profiling of R406 identifies molecular targets underlying the clinical effects of fostamatinib.

Off-target pharmacology may contribute to both adverse and beneficial effects of a new drug. In vitro pharmacological profiling is often applied early in drug discovery; there are fewer reports addressing the relevance of broad profiles to clinical adverse effects. Here, we have characterized the pharmacological profile of the active metabolite of fostamatinib, R406, linking an understanding of drug selectivity to the increase in blood pressure observed in clinical studies. R406 was profiled in a broad range of in vitro assays to generate a comprehensive pharmacological profile and key targets were further investigated using functional and cellular assay systems. A combination of traditional literature searches and text-mining approaches established potential mechanistic links between the profile of R406 and clinical side effects. R406 was selective outside the kinase domain, with only antagonist activity at the adenosine A3 receptor in the range relevant to clinical effects. R406 was less selective in the kinase domain, having activity at many protein kinases at therapeutically relevant concentrations when tested in multiple in vitro systems. Systematic literature analyses identified KDR as the probable target underlying the blood pressure increase observed in patients. While the in vitro pharmacological profile of R406 suggests a lack of selectivity among kinases, a combination of classical searching and text-mining approaches rationalized the complex profile establishing linkage between off-target pharmacology and clinically observed effects. These results demonstrate the utility of in vitro pharmacological profiling for a compound in late-stage clinical development.

The clinical development of sGC modulators, riociguat and vericiguat

Clinical background The NO – sGC – cyclic GMP pathway is a key pathway to regulate vascular tone. Its stimulation leads to vasodilatation; NO deficiency leads to vasoconstriction, inflammation and fibrotic remodelling. Riociguat and vericiguat are two representatives of modulators of the soluble guanylate cyclase and are able to increase cyclic GMP even in conditions of NO deficiency. Riociguat, a first lead sGC stimulator, was developed in two different forms of pulmonary hypertension (PH). PH is a rare, severe disease which untreated has a high morbidity and mortality. It is characterized by endothelial dysfunction, NO deficiency, vascular remodelling and results and devastating increases of the mean pulmonary artery pressure above 25 mm Hg. This condition leads to right heart failure, is associated with impaired exercise capacity and death. Riociguat has been successfully developed in two different forms of PH, pulmonary arterial hypertension (PAH, WHO group 1), and chronic thromboembolic pulmonary hypertension (CTEPH, WHO group 4). It was shown to significantly improve exercise capacity, time to clinical worsening, and also led to meaningful hemodynamic improvements. Riociguat (Trade name: Adempas) is now the first approved medical treatment for patients with CTEPH who are not eligible to undergo surgery, or who have residual disease after pulmonary endarterectomy. Riociguat's ongoing clinical development program includes PH-IIP and diffuse cutaneous sclerodermia, as well as an exploratory study in cystic fibrosis. Vericiguat is currently in late stage clinical development for the treatment of heart failure with reduced and also with preserved ejection fraction (HFrEF and HFpEF). Data from the LEPHT trial with riociguat in patients with PH due to left heart disease hint to the usefulness of sGC modulation in patients with heart failure. The SOCRATRES program studies the efficacy and safety of vericiguat in patients with HFrEF and HFpEF and assesses its effect on ventricular decongestion, as measured by the biomarker NT-pro BNP, and left atrial size. Results of that program will be reported later this year.

Genetic Approaches To Identifying Novel Osteoporosis Drug Targets

During the past two decades effective drugs for treating osteoporosis have been developed, including anti-resorptives inhibiting bone resorption (estrogens, the SERM raloxifene, four bisphosphonates, RANKL inhibitor denosumab) and the anabolic bone forming daily injectable peptide teriparatide. Two potential drugs (odanacatib and romosozumab) are in late stage clinical development. The most pressing unmet need is for orally active anabolic drugs. This review describes the basic biological studies involved in developing these drugs, including the animal models employed for osteoporosis drug development. The genomics revolution continues to identify potential novel osteoporosis drug targets. Studies include human GWAS studies and identification of mutant genes in subjects having abnormal bone mass, mouse QTL and gene knockouts, and gene expression studies. Multiple lines of evidence indicate that Wnt signaling plays a major role in regulating bone formation and continued study of this complex pathway is likely to lead to key discoveries. In addition to the classic Wnt signaling targets DKK1 and sclerostin, LRP4, LRP5/LRP6, SFRP4, WNT16, and NOTUM can potentially be targeted to modulate Wnt signaling. Next-generation whole genome and exome sequencing, RNA-sequencing and CRISPR/CAS9 gene editing are new experimental techniques contributing to understanding the genome. The International Knockout Mouse Consortium efforts to knockout and phenotype all mouse genes are poised to accelerate. Accumulating knowledge will focus attention on readily accessible databases (Big Data). Efforts are underway by the International Bone and Mineral Society to develop an annotated Skeletome database providing information on all genes directly influencing bone mass, architecture, mineralization or strength.

Abstract 3533: Systemic delivery of CTNNB1 Dicer-substrate siRNAs (DsiRNAs) leads to efficient oncogene silencing in diverse tumor types of extra hepatic origin

Abstract The β-catenin/Wnt pathway is consistently activated in human tumors, including >50% of hepatocellular carcinomas (HCC) and >80% of colorectal cancers (CRC). This is often caused directly by tumorigenic mutations in the CTNNB1 gene, which encodes β-catenin protein. Preclinical evidence in genetic cancer models strongly suggests that inhibiting β-catenin function would yield therapeutic benefit to many cancer patients. Since β-catenin is very challenging to target via conventional modalities, no efficacious therapy targeting β-catenin has emerged despite decades of research. RNA interference (RNAi) technology has enabled the inhibition of previously undruggable targets at the mRNA level and has advanced to late-stage clinical development for several indications. However, the clinical application of RNAi has proven to be most successful for targeting mRNAs in the normal liver, and challenges remain with developing formulations that efficiently deliver to extra-hepatic tumors. Here we describe the development and characterization of a platform to treat tumors of diverse primary tissue origin and metastatic location with CTNNB1-targeting DsiRNA. Tumor types tested included xenograft tumors of colorectal origin (CRC), experimental melanoma lung metastases, and difficult-to-transfect leukemia cells which have infiltrated the spleen. In addition to strong silencing of CTNNB1 mRNA, >75% inhibition of tumor growth was observed for a CRC xenograft model. This was achieved by formulating the DisRNA payload in a lipid nanoparticle (LNP) platform termed EnCore (because of its specific Envelope and Core lipid components). EnCore activity against multiple tumors was further improved by optimizing critical cationic lipid and PEG-lipid components. Importantly, studies in knockout mice demonstrate that in vivo tumor activity is independent of Apolipoprotein E, which has been widely described as an essential endogenous ligand for internalization of LNPs into hepatocytes. This strongly suggests that Encore-mediated delivery to tumors in vivo is independent of the ApoE/LDLR system. DCR-MYC, an EnCore-delivered DsiRNA targeting MYC mRNA, is currently in Phase I clinical trials. Further evaluation of LNP-delivered DsiRNAs in PK/PD and efficacy models, including PDX and GEMM will guide a clinical development strategy for CTNNB1 DsiRNA. Citation Format: Shanthi Ganesh, Bo Ying, Martin Koser, Wendy Cyr, Girish Chopda, Hank Dudek, Cheng Lai, Weimin Wang, Bob Brown, Marc T. Abrams. Systemic delivery of CTNNB1 Dicer-substrate siRNAs (DsiRNAs) leads to efficient oncogene silencing in diverse tumor types of extra hepatic origin. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 3533. doi:10.1158/1538-7445.AM2015-3533

Evidence for CVD 103-HgR as an effective single-dose oral cholera vaccine.

We propose the ideal oral cholera vaccine (OCV) should be an inexpensive, single, oral dose that rapidly confers immunity for a long duration, and is well tolerated by individuals vulnerable to cholera. Vaccine trials in industrialized countries of a single oral dose of 5 × 10(8) colony forming units (CFU) of the live, attenuated cholera strain CVD 103-HgR have shown 88-97% serum vibriocidal antibody seroconversion rates, a correlate of protection and documented vaccine efficacy of ≥80% using volunteer challenge studies with wild-type cholera. For individuals of developing countries, a 5 × 10(9) CFU dose of CVD 103-HgR is necessary to elicit similar antibody responses. Presently, a reformulation of CVD 103-HgR is in late-stage clinical development for prospective US FDA licensure; making a cholera vaccine for US travelers potentially accessible in 2016. The availability of CVD 103-HgR should be a welcome addition to the currently available OCVs.

A Proline-Tryptophan Turn in the Intrinsically Disordered Domain 2 of NS5A Protein Is Essential for Hepatitis C Virus RNA Replication

Hepatitis C virus (HCV) nonstructural protein 5A (NS5A) and its interaction with the human chaperone cyclophilin A are both targets for highly potent and promising antiviral drugs that are in the late stages of clinical development. Despite its high interest in regards to the development of drugs to counteract the worldwide HCV burden, NS5A is still an enigmatic multifunctional protein poorly characterized at the molecular level. NS5A is required for HCV RNA replication and is involved in viral particle formation and regulation of host pathways. Thus far, no enzymatic activity or precise molecular function has been ascribed to NS5A that is composed of a highly structured domain 1 (D1), as well as two intrinsically disordered domains 2 (D2) and 3 (D3), representing half of the protein. Here, we identify a short structural motif in the disordered NS5A-D2 and report its NMR structure. We show that this structural motif, a minimal Pro(314)-Trp(316) turn, is essential for HCV RNA replication, and its disruption alters the subcellular distribution of NS5A. We demonstrate that this Pro-Trp turn is required for proper interaction with the host cyclophilin A and influences its peptidyl-prolyl cis/trans isomerase activity on residue Pro(314) of NS5A-D2. This work provides a molecular basis for further understanding of the function of the intrinsically disordered domain 2 of HCV NS5A protein. In addition, our work highlights how very small structural motifs present in intrinsically disordered proteins can exert a specific function.

Abstract B44: Pharmacologic inhibition with IPI-145 and genetic inhibition of PI3K p110δ antagonizes intrinsic and extrinsic survival signals in chronic lymphocytic leukemia

Abstract Chronic lymphocytic leukemia (CLL), the most common adult leukemia in the western world, remains an incurable B-cell malignancy. It is characterized by the accumulation of malignant mature B cells in the blood, lymph nodes, spleen and bone marrow. CLL cells display up-regulated B cell receptor (BCR) activation, which maintains B cell survival and proliferation through transmitting microenvironmental stimuli. Due to aberrant regulation of the BCR, CLL cells display constitutively activated survival and proliferation pathways, such as phosphoinositide-3 kinase (PI3K) and Bruton's tyrosine kinase (BTK) pathways. Small molecules that target such kinases in the BCR pathway have shown significant clinical activity in CLL patients. The PI3K p110δ inhibitor, idelalisib, was granted a breakthrough therapy designation by the FDA in relapsed CLL and the BTK inhibitor, ibrutinib, has received approval by FDA for treatment of relapsed CLL. However, patients still relapse on these therapies. Here we use pharmacologic and genetic approaches to further characterize the role of PI3K signaling in the leukemia pathogenesis in the CLL cell and in the microenvironment. We describe that a PI3K p110δ and p110γ inhibitor, IPI-145, which is in late stage clinical development, attenuates pro-survival signals in the OSU-CLL cell line and primary human and murine CLL cells and promotes apoptosis and downstream pathway inactivation in primary human and murine CLL cells in a dose- and time-dependent fashion. To examine the cytotoxicity of IPI-145 in normal immune cells, we incubated whole blood from CLL patients with 0.25-5 μM IPI-145 for 48 hours and analyzed by flow cytometry for absolute count of live CD3+ T cells, CD56+ NK cells and CD19+ B cells. T cells and NK cells were sensitive to IPI-145, displaying about 20% decrease in viability at concentrations greater than 0.5μM, however the B cell population showed about 50% decrease in viability. To specifically examine normal B cells, we isolated CD19+ B cells from healthy volunteer blood and incubated with 1 μM IPI-145 for 48 hours and observed no cytotoxicity, despite observing a significant decrease in CLL cells viability under the same conditions. Additionally, IPI-145 is highly effective at reducing downstream PI3K signaling in a B cell line with the ibrutinib resistance conferring BTK C481S mutation. Genetically we show that the PI3K p110δ-inactivating and the TCL1 leukemia murine models can be utilized to further explore the differential role of PI3K p110δ in leukemic cell and microenvironment. Our study indicates that systemic disruption of PI3K p110δ function in the TCL1 mouse significantly prevents spontaneous leukemia development, indicating that PI3K p110δ is a critical kinase for CLL disease initiation and expansion. Moreover, inactivation of PI3K p110δ in the microenvironment showed a dose dependent effect in delaying leukemia engraftment. This suggests that PI3K p110δ activity is also critical in the non-B cell compartment for leukemia progression. While our group has focused on the role of PI3K p110δ, we continue to examine the role of PI3K p110γ using the PI3K p110δ and p110γ inhibitor, IPI-145. This study provides solid rationale for ongoing clinical development of IPI-145 in CLL patients. Additionally, as IPI-145 can continue to inhibit the PI3K/AKT pathway in the setting of a C481S BTK mutation, it provides justification for clinical studies of this agent in this subset of patients. Citation Format: Amy J. Johnson, Shuai Dong, Daphne Guinn, Jason A. Dubovsky, Yiming Zhong, Amy Lehman, Jeff Kutok, Jennifer A. Woyach, John C. Byrd. Pharmacologic inhibition with IPI-145 and genetic inhibition of PI3K p110δ antagonizes intrinsic and extrinsic survival signals in chronic lymphocytic leukemia. [abstract]. In: Proceedings of the AACR Special Conference: Targeting the PI3K-mTOR Network in Cancer; Sep 14-17, 2014; Philadelphia, PA. Philadelphia (PA): AACR; Mol Cancer Ther 2015;14(7 Suppl):Abstract nr B44.

Cannabis-Derived Pharmaceuticals

Cannabis, commonly known as marijuana, weed or pot, is a natural product derived from the Cannabis sativa plant. It has been used medicinally for thousands of years. Recent legislation allowing the use of medical marijuana in over 23 US states has spurred interest in developing pharmaceutical-derived Cannabis products to treat a variety of clinical indications ranging from pain relief to epilepsy. Many products are in late stage clinical development in the US and elsewhere. This article reviews the medicinal properties of Cannabis and describes pharmaceutical-derived Cannabis products that are currently being developed for theUS market.Â

Public Funding of Clinical-Stage Antibiotic Development in the United States and European Union

The health and national security challenge of antibiotic resistance has led governments to adopt policies to stimulate new antibiotic R&D. Government programs that directly fund late-stage clinical development of antibiotics have emerged, including the Broad Spectrum Antimicrobial Program of the Biomedical Advanced Research and Development Authority in the United States, and the New Drugs for Bad Bugs program of the Innovative Medicines Initiative in the European Union. These efforts are collectively investing nearly $1 billion and are supporting nearly 20% of the global antibiotic pipeline. This article describes these programs, including the antibiotics and their targeted pathogens and clinical indications, as well as program mechanisms for project eligibility, selection, governance, funding, and IP management. Preliminary assessment of the impact of these mechanisms on the success of the programs is provided.

Validation of Sensititre Dry-Form Broth Microdilution Panels for Susceptibility Testing of Ceftazidime-Avibactam, a Broad-Spectrum-β-Lactamase Inhibitor Combination.

Ceftazidime-avibactam is a broad-spectrum-β-lactamase inhibitor combination in late-stage clinical development for the treatment of serious infections. In preparation for clinical microbiology laboratory use, a validation experiment was initiated to evaluate a commercial broth microdilution product (Sensititre dried MIC susceptibility system) compared to reference panels using 525 recent clinical isolates. Among 11 pathogen groups, all had Sensititre MIC/reference MIC ratios predominantly at 1 (47.5% to 97.5%), and automated and manual endpoint results did not differ. Enterobacteriaceae MIC comparisons showed a modest skewing of Sensititre MIC results toward an elevated MIC (33.9%), but the essential agreement was 98.9% with 100.0% reproducibility. In conclusion, Sensititre panels produced accurate ceftazidime-avibactam MIC results, allowing quality MIC guidance for therapy following regulatory approvals.

Abstract P1-17-02: Adaptive and acquired mechanisms of resistance to PI3K inhibitors

Abstract Background: Activation of PI3K alpha is among the most frequent oncogenic events in breast transformation, commonly occurring through mutations in the p110 alpha subunit of PI3K or amplification of the HER2 receptor tyrosine kinase. Therapeutic targeting of activated PI3K signaling has been made feasible by the development of highly selective and potent ATP competitive inhibitors of p110 alpha some of which are in late stage clinical development. Unfortunately, clinical response to these compounds has not been seen for the majority of patients and when response occurs it is often short-lived. We have hypothesized that relief of feedback regulation of PI3K signaling constitutes a major mechanism for tumor cell adaptation to inhibitors of oncogenes such as PI3K. Methods: To understand the basis for resistance to PI3K inhibitors we studied the consequences of acute and prolonged PI3K inhibition in patient samples as well as in cell line and murine models of breast cancer. We examined the effects of selective inhibition of PI3K alpha on upstream and parallel signaling pathway components utilizing several phosphoproteomic methods including mass spectrometry, antibody microarrays, and immunoblotting. We further investigated the consequences of PI3K inhibition upon the genome using next generation sequencing. Results: In the context of tumors with high levels of RTK signaling such as HER2+ breast cancers, inhibitors of PI3K alpha led to only transient inhibition of PI3K/AKT signaling with reactivation of signaling closely coinciding in time with loss of feedback suppression of RTKs such as HER3 and IGF1R. This reactivation of AKT signaling could be blocked using inhibitors of the induced RTKs and this was associated with a marked increase in tumor cell death. A second mechanism of reactivation of PI3K signaling was observed in examining the genomes of tumors where inhibition of PI3K alpha was associated with acquired inactivating mutations in PTEN. Loss of PTEN in such tumors was associated with failure of the PI3K alpha inhibitor to block PI3K/AKT signaling but sensitivity to combined PI3K alpha plus PI3K beta inhibition in laboratory models. Finally, in the context of hormone dependent tumor models, inhibition of PI3K alpha was associated with an increase in estrogen receptor activation. This was observed as increases in ER protein expression, ER phosphorylation, and ER binding to established ER target promoters. Combined inhibition of ER and PI3K alpha was demonstrated to be synergistic in these models in vivo. Conclusions: Feedback suppression of upstream and parallel signaling pathways poses a major limitation to the antitumor effects of single agent PI3K alpha inhibition. Combination approaches to potently inhibit PI3K alpha, PI3K beta, and either ER or HER3/IGF1R may prove more effective and durable in the clinic. Citation Format: Sarat Chandarlapaty, Maurizio Scaltriti, Marie Will, Zhiqiang Li, Ana Bosch-Campos, Sarit Schwartz, Vanessa Rodrik-Outmezguine, Michael Berger, Baselga Jose, Neal Rosen. Adaptive and acquired mechanisms of resistance to PI3K inhibitors [abstract]. In: Proceedings of the Thirty-Seventh Annual CTRC-AACR San Antonio Breast Cancer Symposium: 2014 Dec 9-13; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2015;75(9 Suppl):Abstract nr P1-17-02.

TKI Resistance for T790M Mutation

表皮生长因子受体（epidermal growth factor receptor, EGFR）的口服活性小分子抑制剂的开发为非小细胞肺癌（non-small cell lung cancer, NSCLC）提供了新的治疗方案。EGFR基因发生激活突变的患者对EGFR酪氨酸激酶抑制剂（epidermal growth factor receptor tyrosine kinase inhibitors, EGFR-TKIs）治疗敏感，该疗法使大量患者临床获益。第一代可逆型ATP-竞争型EGFR-TKIs，吉非替尼和厄洛替尼作为一线、二线或维持疗法具有疗效。尽管这些药物具有初始疗效，但大多数患者在1年内会产生抗药性，50%-60%的患者都与T790M管家基因出现突变有关。新近的不可逆型EGFR-TKIs-阿法替尼和dacomitinib可共价结合并抑制多个ErbB家族的受体（EGFR、HER2和HER4）。人们主要评价这些药物作为一线治疗的意义，以及在对第一代EGFR-TKIs产生获得性抗药性情况下的意义。阿法替尼是获批的第一种ErbB家族阻断剂，用于治疗带有EGFR激活突变的NSCLC患者；dacomitinib正处在临床开发的后期阶段。特异性靶向T790M抗药性突变的EGFR抑制剂（AZD9291、CO-1686、HM61713）正处在早期开发阶段。正如本文中的讨论，EGFR-TKIs靶向的激酶范围不同，它们结合EGFR受体的可逆性和药物相互作用的潜能也不同。对于临床医生来说，这些差异对经多种药物治疗的NSCLC患者具有意义，从创新型抗癌药物联合治疗策略的角度看，这些差异也极具意义。

Safety and Pharmacokinetics of Solithromycin in Subjects with Hepatic Impairment.

Solithromycin, a new macrolide and the first fluoroketolide, is in late-stage clinical development and, like older macrolides, is primarily metabolized and excreted through liver-dependent mechanisms. This study evaluated the safety and pharmacokinetics of solithromycin in patients with chronic liver disease. This open-label, multiple-dose study in subjects with hepatic impairment and in healthy control subjects (matched for age, weight, and sex) enrolled 8 Child-Pugh class A (mild), 8 class B (moderate), and 8 class C (severe) patients and 9 healthy controls. Subjects (n = 33) received one 800-mg dose on day 1 followed by once-daily doses of 400 mg on days 2 through 5. The most commonly reported adverse events were mild diarrhea and mild headache, and no significant differences were noted between hepatically impaired subjects and healthy controls. The pharmacokinetics of plasma solithromycin in subjects with mild and moderate impairment was similar to that in control subjects. In subjects with severe impairment, total exposure to solithromycin at steady state (area under the plasma concentration-time curve [AUC0-tau]) was decreased compared to that in control subjects, which may have been related to the higher body mass index of individuals in this group. No greater accumulation was noted in any hepatically impaired cohort on day 5 compared to that in control subjects. No decrease in dosage is therefore needed when administering solithromycin to patients with mild, moderate, or severe hepatic impairment. Solithromycin was well tolerated in this patient population, and no significant differences in safety, compared to healthy controls, were noted.

Professor Jon Wigginton: where we are standing in immunotherapy.

Prof. Jon Wigginton (Figure 1) was previously the Therapeutic Area Head, Immuno-Oncology, Early Clinical Research and Executive Director, Discovery Medicine- Clinical Oncology at Bristol-Myers Squibb (BMS), where he led the early clinical development of the BMS Immuno- Oncology portfolio including anti-PD-1 and anti-PD-L1. Prior to joining BMS, Dr. Wigginton was the Director of Clinical Oncology at Merck Research Laboratories, where he led early- and late-stage clinical development teams for small molecules and biologics. During his academic career, he held several positions at the National Cancer Institute Center for Cancer Research (NCI-CCR), including Head of Investigational Biologics Section, Pediatric Oncology Branch. Dr. Wigginton is also past president of the International Society for the Biological Therapy of Cancer (now SITC). He is the author of over 50 manuscripts and reviews and is the recipient of multiple awards for scientific accomplishment from sources including the NIH, NCI, USPHS, iSBTc, ISICR, Children’s Cancer Foundation, Merck and BMS. Dr. Wigginton received his M.D. and B.S. in Biology, with distinction, from the University of Michigan.

Combining active immunotherapy and immune checkpoint inhibitors in prostate cancer.

172 Background: Results of recent clinical trials have intensified interest in immunotherapy in oncology. A number of cancer immunotherapies have been approved recently, while others are in late stage clinical development. The poxvirus-based active immunotherapy, PROSTVAC is generally well tolerated and is currently being evaluated in a global Phase 3 randomized, placebo-controlled trial. Ipilimumab, an approved immune checkpoint inhibitor in melanoma, is also being evaluated in a Phase 3 trial in chemo-naïve mCRPC. Methods: Results of two Phase 2 trials in men with mCRPC who were treated with PROSTVAC alone were compared with results from a Phase 1 combination study in mCRPC patients treated with PROSTVAC plus escalating doses of ipilimumab. Patients were enrolled in the Phase 1 combination study when docetaxel was the only FDA-approved mCRPC treatment that improved overall survival (OS). Results: In a multicenter Phase 2 trial, 125 men were randomized 2:1 to receive PROSTVAC or placebo. Patients treated with PROSTVAC had improved OS compared to placebo (25.1 vs 16.6 months; HR 0.56; 95% CI 0.37-0.85).Similar data was seen in a second phase 2 trial of PROSTVAC, where 32 patients with mCRPC had a median OS of 26.6 months (predicted median OS by the Halabi nomogram was 17.4 months). In a Phase 1 combination study of 30 mCRPC patients with similar baseline characteristics (predicted median OS of 18.5 months), patients were treated with PROSTVAC plus escalating doses of ipilimumab. The observed median OS was 31.3 months for all dose cohorts and 37.2 months for patients treated at 10 mg/kg based on updated overall survival data. Furthermore, there appears to be a tail on the curve with approximately 20% of patients at 10 mg/kg alive at 80 months. Conclusions: The comparison of data from three independent trials of PROSTVAC active immunotherapy in three similar patient populations provides hypothesis-generating data that the addition of an immune checkpoint inhibitor may have a positive effect on overall survival through a potential synergy in mechanism of action. The updated long term survival data is further evidence of improved OS with PROSTVAC. Future randomized trials are being planned to prospectively evaluate this hypothesis. Clinical trial information: NCT00113984.

Evaluation of program success for programs with multiple trials in binary outcomes.

A late-stage clinical development program typically contains multiple trials. Conventionally, the program's success or failure may not be known until the completion of all trials. Nowadays, interim analyses are often used to allow evaluation for early success and/or futility for each individual study by calculating conditional power, predictive power and other indexes. It presents a good opportunity for us to estimate the probability of program success (POPS) for the entire clinical development earlier. The sponsor may abandon the program early if the estimated POPS is very low and therefore permit resource savings and reallocation to other products. We provide a method to calculate probability of success (POS) at an individual study level and also POPS for clinical programs with multiple trials in binary outcomes. Methods for calculating variation and confidence measures of POS and POPS and timing for interim analysis will be discussed and evaluated through simulations. We also illustrate our approaches on historical data retrospectively from a completed clinical program for depression.