Trends in the approval of cancer therapies by the FDA in the twenty-first century

The cancer treatment landscape has changed dramatically since the turn of the century, resulting in substantial improvements in outcomes for patients. This Review summarizes trends in the approval of oncology therapeutic products by the United States Food and Drug Administration (FDA) from January 2000 to October 2022, based on a categorization of these products by their mechanism of action and primary target. Notably, the rate of oncology indication approvals has increased in this time, driven by approvals for targeted therapies, as has the rate of introduction of new therapeutic approaches. Kinase inhibitors are the dominant product class by number of approved products and indications, yet immune checkpoint inhibitors have the second most approvals despite not entering the market until 2011. Other trends include a slight increase in the share of approvals for biomarker-defined populations and the emergence of tumour-site-agnostic approvals. Finally, we consider the implications of the trends for the future of oncology therapeutic product development, including the impact of novel therapeutic approaches and technologies.

Use of Single-Arm Trials for US Food and Drug Administration Drug Approval in Oncology, 2002-2021

Importance

Single-arm trials have allowed for transformative therapies to be made available to patients expeditiously. However, using single-arm trials to support drug approval presents several challenges that must be carefully considered.

Observations

Between January 1, 2002, and December 31, 2021, the US Food and Drug Administration granted 176 new malignant hematology and oncology indications based on single-arm trials, including 116 accelerated approvals (AAs) and 60 traditional approvals. Overall, 87 approvals (49%) were for new molecular entities or original biologics and 89 (51%) were supplemental indications. Response rate (RR) was the most common end point used to support approval in these single-arm trials (173 of 176 [98%]). Of the 116 AAs based on single-arm trials, 45 (38%) fulfilled their postmarketing requirement to verify clinical benefit, 61 (52%) are pending verification of benefit, and 10 (9%) were withdrawn from the market as of December 31, 2021. Most (56 of 61 [92%]) AAs based on single-arm trials pending verification of benefit occurred during the previous 5 years and have ongoing confirmatory trials as of December 2021.

Conclusions and Relevance

Single-arm trials have been a common development strategy to support regulatory approval as early-stage expansion cohorts with promising durable RRs have become more prevalent. In the appropriate context, single-arm trials using durable RRs can allow patients expedited access to novel therapies and will continue to serve a role in advancing drug development in oncology. However, single-arm trials have a smaller noncomparative safety data set, inability to use time-to-event end points, and other limitations that require careful consideration within the context of the disease and available therapies. The randomized clinical trial remains the preferred approach in clinical investigation.

Emerging oncology drug targets in the 21st century: An FDA analysis

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Background: Traditional chemotherapy agents are cytotoxic and typically act on all rapidly dividing cells. In contrast, targeted cancer therapies take advantage of unique genetic or proteomic susceptibility in cancer cells, their microenvironment, or the immune system to selectively target tumor tissue or stimulate immune activity. We catalogued oncology drug approvals in the U.S. in the 21st century to study the evolution of molecular targets over the last twenty years. Methods: We used internal FDA databases and data repositories to generate a dataset of all oncology approvals granted 1/1/2000-12/31/2019. This dataset was curated through a comprehensive survey of drug labels, drug reviews, and published literature to include target gene(s), mechanism of action, drug class, and approved indications for each drug. Approvals were grouped into five-year periods for trend analyses. Results: There has been an increase in the number of oncology approvals over the last twenty years, the vast majority of which are targeted therapies. There have been considerable recent advances in some disease sites. Three disease sites (ovary, bladder, and liver) had many approvals in the last five years after few to none 2000-2014; lung cancer and melanoma have seen substantial advances in the last ten years. Additionally, the first site-agnostic approvals occurred in the last five years. Kinase inhibitors are the most common drug class by both number of drugs and indications. Immune checkpoint inhibitors (ICI) are the second most common class by number of indications, despite having only entered the market in 2011 and being the sixth most common class by number of drugs. The target gene PD-1 has the highest number of approved indications, followed by EGFR and the BCR-ABL fusion gene. The number of novel genes targeted by drugs approved in 2010-2019 is nearly double that of 2000-2009, with the most novel gene targets in 2019 (n = 7). Conclusions: This analysis captures the landscape of targeted drug approvals in the 21st century, including the continued dominance of kinase inhibitors despite the dramatic impact of ICIs on cancer care since their introduction in 2011. The promise of targeted therapy in oncology is especially evident from the introduction of site-agnostic indications, new approvals in cancer types with limited therapy options, and ICIs with many indications due to targeting tumors indirectly via the immune system. The continual introduction of novel gene targets provides a snapshot of ongoing novel drug development, and it will be interesting to see whether this trend continues over the next twenty years.

Differentiation Syndrome with Ivosidenib and Enasidenib Treatment in Patients with Relapsed or Refractory IDH-Mutated AML: A U.S. Food and Drug Administration Systematic Analysis

PURPOSE

Differentiation syndrome (DS) is a serious adverse reaction of isocitrate dehydrogenase (IDH) inhibitors ivosidenib and enasidenib in patients with (IDH)1- and IDH2-mutated acute myeloid leukemia (AML), respectively.

EXPERIMENTAL DESIGN

During FDA review of marketing applications for ivosidenib and enasidenib, data from pivotal trials were queried to identify cases of DS in patients with relapsed or refractory (R/R) AML. One hundred seventy-nine patients with R/R AML received ivosidenib and 214 received enasidenib. Adverse events, labs, and vital signs in the first 90 days of treatment were screened per diagnostic criteria, and narratives were reviewed to adjudicate DS cases.

RESULTS

We identified 72 of 179 (40%) potential cases for ivosidenib and 86 of 214 (40%) for enasidenib; 34 of 179 (19%) and 41 of 214 (19%) were adjudicated as DS. Leukocytosis was present in 79% and 61% of cases, respectively. Median (range) time to onset was 20 (1-78) and 19 (1-86) days. Grade ≥ 3 adverse reactions occurred in 68% and 66%; 6% and 5% were fatal. Univariate analyses suggested baseline bone marrow blasts ≥ 48% and peripheral blood blasts ≥ 25% and 15% for ivosidenib and enasidenib, respectively, were associated with increased risk of DS. Complete remission (CR) + CR with partial hematologic recovery rates were lower in patients with versus without DS [ivosidenib 18% (95% confidence interval, 7%-35%) vs. 36% (28%-45%); enasidenib 18% (7%-33%) vs. 25% (18%-32%)].

CONCLUSIONS

DS is a common and potentially fatal adverse reaction of IDH inhibitors, and use of standardized diagnostic criteria may aid in earlier diagnosis and treatment.See related commentary by Zeidner, p. 4174.

How to Train Your T Cells: Overcoming Immune Dysfunction in Multiple Myeloma

The progression of multiple myeloma, a hematologic malignancy characterized by unregulated plasma cell growth, is associated with increasing innate and adaptive immune system dysfunction, notably in the T-cell repertoire. Although treatment advances in multiple myeloma have led to deeper and more durable clinical responses, the disease remains incurable for most patients. Therapeutic strategies aimed at overcoming the immunosuppressive tumor microenvironment and activating the host immune system have recently shown promise in multiple myeloma, particularly in the relapsed and/or refractory disease setting. As the efficacy of T-cell-dependent immuno-oncology therapy is likely affected by the health of the endogenous T-cell repertoire, these therapies may also provide benefit in alternate treatment settings (e.g., precursor disease; after stem cell transplantation). This review describes T-cell-associated changes during the evolution of multiple myeloma and provides an overview of T-cell-dependent immuno-oncology approaches under investigation. Vaccine and checkpoint inhibitor interventions are being explored across the multiple myeloma disease continuum; treatment modalities that redirect patient T cells to elicit an anti-multiple myeloma response, namely, chimeric antigen receptor (CAR) T cells and bispecific antibodies [including BiTE (bispecific T-cell engager) molecules], have been primarily evaluated to date in the relapsed and/or refractory disease setting. CAR T cells and bispecific antibodies/antibody constructs directed against B-cell maturation antigen have generated excitement, with clinical data demonstrating deep responses. An increased understanding of the complex interplay between the immune system and multiple myeloma throughout the disease course will aid in maximizing the potential for T-cell-dependent immuno-oncology strategies in multiple myeloma.

Abstract 3516: A genomics model to predict immune-related adverse events in cancer patients treated with checkpoint inhibitors

The overall objective of this study is to use next-generation sequencing technology and bioinformatics to better inform the safety of immunotherapy treatment for cancer. Cancer patients commonly develop immune-related adverse events (irAEs) during and after treatment with checkpoint inhibitors. These irAEs can be serious or even fatal. Therefore, a biomarker for prediction of irAE development could have utility for heightened surveillance, personalized therapy decisions, and regulatory evaluation of drugs. Due to the similarity between irAEs and autoimmune diseases and the high heritability of autoimmune diseases, we hypothesized that certain patients could have a genetic predisposition for developing irAEs. To test this hypothesis, we conducted whole exome sequencing on an Illumina NextSeq to interrogate germline genomes of solid tumor patients (n=50) treated with an anti-PD-L1 antibody (NCT01772004). Relevant clinical data, such as adverse events and irAE classification, were provided for this retrospective analysis; twenty percent of patients (10/50) had irAEs. A preliminary germline genetic model of irAEs was constructed using short variant calls from this initial training set. This was generated using a proprietary algorithm that implements a Monte-Carlo simulation expansion of Fisher’s regularized linear discriminant analysis (RLDA) in a multidimensional measurement system to create a model that maximizes separation between two groups. This model consists of 131 genes, each of which make a relatively small contribution to the overall signature. The ten genes with the highest contribution coefficients together account for 21% of the signature. Ingenuity Pathway Analysis (IPA) identified a network associated with infectious diseases, antimicrobial response, and inflammatory response that contains 21 interconnected genes from the signature. IPA also revealed that genes in the signature have a variety of molecular and cellular functions, the most significant of which are cell death and survival, cellular movement, and cell-to-cell signaling and interaction. This model has 100% sensitivity, specificity, and accuracy on the training set. Future directions will test the performance of this putative genomic model on a new dataset to assess the validity and utility of the model as a predictive biomarker to identify patients at risk for developing irAEs in response to checkpoint inhibition.

Citation Format: Emma C. Scott, Dickran Kazandjian, Luis Santana-Quintero, Tigran Ghazanchyan, Svetlana Petrovskaya, Yong Zhang, Amy Rosenberg, V. Ashutosh Rao, Jennifer L. Marte, Gideon M. Blumenthal, Marc R. Theoret, Richard Pazdur, James L. Gulley, Julia A. Beaver. A genomics model to predict immune-related adverse events in cancer patients treated with checkpoint inhibitors [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2019; 2019 Mar 29-Apr 3; Atlanta, GA. Philadelphia (PA): AACR; Cancer Res 2019;79(13 Suppl):Abstract nr 3516.

Staging Systems for Newly Diagnosed Myeloma Patients Undergoing Autologous Hematopoietic Cell Transplantation: The Revised International Staging System Shows the Most Differentiation between Groups

The Revised International Staging System (R-ISS) and the International Myeloma Working Group 2014 (IMWG 2014) are newer staging systems used to prognosticate multiple myeloma (MM) outcomes. We hypothesized that these would provide better prognostic differentiation for newly diagnosed multiple myeloma (MM) compared with ISS. We analyzed the Center for International Blood and Marrow Transplant Research database from 2008 to 2014 to compare the 3 systems (N = 628) among newly diagnosed MM patients undergoing upfront autologous hematopoietic cell transplantation (AHCT). The median follow-up of survivors was 48 (range, 3 to 99) months. The R-ISS provided the greatest differentiation between survival curves for each stage (for overall survival [OS], the differentiation was 1.74 using the R-ISS, 1.58 using ISS, and 1.60 using the IMWG 2014) . Univariate analyses at 3 years for OS showed R-ISS I at 88% (95% confidence interval [CI], 83% to 93%), II at 75% (95% CI, 70% to 80%), and III at 56% (95% CI, 3% to 69%; P < .001). An integrated Brier score function demonstrated the R-ISS had the best prediction for PFS, though all systems had similar prediction for OS. Among available systems, the R-ISS is the most optimal among available prognostic tools for newly diagnosed MM undergoing AHCT. We recommend that serum lactate dehydrogenase and cytogenetic data be performed on every MM patient at diagnosis to allow accurate prognostication.

Daratumumab plus bortezomib and dexamethasone versus bortezomib and dexamethasone in relapsed or refractory multiple myeloma: updated analysis of CASTOR

Daratumumab, a CD38 human monoclonal antibody, demonstrated significant clinical activity in combination with bortezomib and dexamethasone versus bortezomib and dexamethasone alone in the primary analysis of CASTOR, a phase 3 study in relapsed and/or refractory multiple myeloma. A post hoc analysis based on treatment history and longer follow up is presented. After 19.4 (range: 0–27.7) months of median follow up, daratumumab plus bortezomib and dexamethasone prolonged progression-free survival (median: 16.7 versus 7.1 months; hazard ratio, 0.31; 95% confidence interval, 0.24-0.39; P<0.0001) and improved the overall response rate (83.8% versus 63.2%; P<0.0001) compared with bortezomib and dexamethasone alone. The progression-free survival benefit of daratumumab plus bortezomib and dexamethasone was most apparent in patients with 1 prior line of therapy (median: not reached versus 7.9 months; hazard ratio, 0.19; 95% confidence interval, 0.12-0.29; P<0.0001). Daratumumab plus bortezomib and dexamethasone was also superior to bortezomib and dexamethasone alone in subgroups based on prior treatment exposure (bortezomib, thalidomide, or lenalidomide), lenalidomide-refractory status, time since last therapy (≤12, >12, ≤6, or >6 months), or cytogenetic risk. Minimal residual disease–negative rates were >2.5-fold higher with daratumumab across subgroups. The safety profile of daratumumab plus bortezomib and dexamethasone remained consistent with longer follow up. Daratumumab plus bortezomib and dexamethasone demonstrated significant clinical activity across clinically relevant subgroups and provided the greatest benefit to patients treated at first relapse. Trial registration: clinicaltrials.gov identifier: 02136134.

Bortezomib-based Chemotherapy for Multiple Myeloma Patients Without Comorbid Cardiovascular Disease Shows No Cardiotoxicity

BACKGROUND

Proteasome inhibitors used in the treatment of multiple myeloma act primarily through the disruption of intrinsic cellular protein quality maintenance, resulting in proteotoxic stress, cellular dysfunction, and, ultimately, cell death. We assessed whether evidence has shown off-target myocardial dysfunction related to the administration of bortezomib-based chemotherapy for multiple myeloma.

PATIENTS AND METHODS

Patients aged 18 to 70 years who were free of significant cardiovascular disease were included. They underwent evaluations before and after each dose of bortezomib to assess for clinical, subclinical, and transient cardiotoxicity using echocardiography and serum biomarker measurement. Cardiac magnetic resonance imaging was performed at 3 separately defined intervals. The primary modality for determining subclinical myocardial dysfunction was echocardiographic assessment of the global longitudinal strain (GLS).

RESULTS

Eleven patients (7 men) with an average age of 55 years were included. No evidence of cumulative myocardial dysfunction was found using echocardiographic markers, primarily GLS (average change in absolute GLS, -1.17; P = .064). Additionally, no echocardiographic evidence of transient cardiotoxicity was found. The left ventricular ejection fraction (LVEF) also did not show any significant changes (ΔLVEF, -2.17%; P = .15). Magnetic resonance imaging confirmed no changes in structure or function (ΔLVEF, -2.6%; P = .54) and extracellular volume fraction (Δ = 2%; P = .46). The serum biomarker levels also did not change significantly over time.

CONCLUSION

We did not observe cardiotoxicity from bortezomib-based chemotherapy despite very intensive evaluation with multiple modalities. Neither cumulative nor transient alterations were found in our metrics, suggesting that bortezomib is safe from a cardiovascular standpoint for patients free of cardiovascular disease.

The Mobile Element Locator Tool (MELT): population-scale mobile element discovery and biology

Mobile element insertions (MEIs) represent ∼25% of all structural variants in human genomes. Moreover, when they disrupt genes, MEIs can influence human traits and diseases. Therefore, MEIs should be fully discovered along with other forms of genetic variation in whole genome sequencing (WGS) projects involving population genetics, human diseases, and clinical genomics. Here, we describe the Mobile Element Locator Tool (MELT), which was developed as part of the 1000 Genomes Project to perform MEI discovery on a population scale. Using both Illumina WGS data and simulations, we demonstrate that MELT outperforms existing MEI discovery tools in terms of speed, scalability, specificity, and sensitivity, while also detecting a broader spectrum of MEI-associated features. Several run modes were developed to perform MEI discovery on local and cloud systems. In addition to using MELT to discover MEIs in modern humans as part of the 1000 Genomes Project, we also used it to discover MEIs in chimpanzees and ancient (Neanderthal and Denisovan) hominids. We detected diverse patterns of MEI stratification across these populations that likely were caused by (1) diverse rates of MEI production from source elements, (2) diverse patterns of MEI inheritance, and (3) the introgression of ancient MEIs into modern human genomes. Overall, our study provides the most comprehensive map of MEIs to date spanning chimpanzees, ancient hominids, and modern humans and reveals new aspects of MEI biology in these lineages. We also demonstrate that MELT is a robust platform for MEI discovery and analysis in a variety of experimental settings.

Targeting the programmed cell death 1 pathway in Hodgkin lymphoma: the place of nivolumab

Nivolumab is a humanized immunoglobulin gamma-4 kappa anti-programmed cell death 1 monoclonal antibody that is currently approved in the treatment of several solid tumors and recently gained accelerated approval in classical Hodgkin lymphoma (cHL) that has relapsed or progressed following autologous hematopoietic stem-cell transplantation and post-transplantation brentuximab vedotin. The purpose of this article is to review the immunophysiologic basis, clinical efficacy, and toxicity of nivolumab in the treatment of cHL. In addition, we will review ongoing clinical trials and potential future directions of checkpoint inhibition in the treatment of cHL.

Management of relapsed and refractory multiple myeloma in modern times: Incorporating new agents into decision-making

Although upfront treatment of multiple myeloma has become more effective, relapses are the norm, often driven by the emergence of a genetically divergent clone selected by the initial therapy. Recent trials have demonstrated the safety and efficacy of combination therapy also in the relapsed and refractory setting and supported the regulatory approval of several new agents including new proteasome inhibitors, immunomodulatory agents, and monoclonal antibodies. We provide a detailed summary of recent practice-changing trials in relapsed and refractory MM and share a practical approach to assimilate disease and patient-features into treatment decision. Am. J. Hematol. 91:1044-1051, 2016. © 2016 Wiley Periodicals, Inc.

Post-Transplant Outcomes in High-Risk Compared with Non-High-Risk Multiple Myeloma: A CIBMTR Analysis

Conventional cytogenetics and interphase fluorescence in situ hybridization (FISH) identify high-risk multiple myeloma (HRM) populations characterized by poor outcomes. We analyzed these differences among HRM versus non-HRM populations after upfront autologous hematopoietic cell transplantation (autoHCT). Between 2008 and 2012, 715 patients with multiple myeloma identified by FISH and/or cytogenetic data with upfront autoHCT were identified in the Center for International Blood and Marrow Transplant Research database. HRM was defined as del17p, t(4;14), t(14;16), hypodiploidy (<45 chromosomes excluding -Y) or chromosome 1 p and 1q abnormalities; all others were non-HRM. Among 125 HRM patients (17.5%), induction with bortezomib and immunomodulatory agents (imids) was higher compared with non-HRM (56% versus 43%, P < .001) with similar pretransplant complete response (CR) rates (14% versus 16%, P .1). At day 100 post-transplant, at least a very good partial response was 59% in HRM and 61% in non-HRM (P = .6). More HRM patients received post-transplant therapy with bortezomib and imids (26% versus 12%, P = .004). Three-year post-transplant progression-free (PFS) and overall survival (OS) rates in HRM versus non-HRM were 37% versus 49% (P < .001) and 72% versus 85% (P < .001), respectively. At 3 years, PFS for HRM patients with and without post-transplant therapy was 46% (95% confidence interval [CI], 33 to 59) versus 14% (95% CI, 4 to 29) and in non-HRM patients with and without post-transplant therapy 55% (95% CI, 49 to 62) versus 39% (95% CI, 32 to 47); rates of OS for HRM patients with and without post-transplant therapy were 81% (95% CI, 70 to 90) versus 48% (95% CI, 30 to 65) compared with 88% (95% CI, 84 to 92) and 79% (95% CI, 73 to 85) in non-HRM patients with and without post-transplant therapy, respectively. Among patients receiving post-transplant therapy, there was no difference in OS between HRM and non-HRM (P = .08). In addition to HRM, higher stage, less than a CR pretransplant, lack of post-transplant therapy, and African American race were associated with worse OS. In conclusion, we show HRM patients achieve similar day 100 post-transplant responses compared with non-HRM patients, but these responses are not sustained. Post-transplant therapy appeared to improve the poor outcomes of HRM.

Small molecule inhibitor screen identifies synergistic activity of the bromodomain inhibitor CPI203 and bortezomib in drug resistant myeloma

Purpose

Despite significant therapeutic progress in multiple myeloma, drug resistance is uniformly inevitable and new treatments are needed. Our aim was to identify novel, efficacious small-molecule combinations for use in drug resistant multiple myeloma.

Experimental Design

A panel of 116 small molecule inhibitors was used to screen resistant myeloma cell lines for potential therapeutic targets. Agents found to have enhanced activity in the bortezomib or melphalan resistant myeloma cell lines were investigated further in combination. Synergistic combinations of interest were evaluated in primary patient cells.

Results

The overall single-agent drug sensitivity profiles were dramatically different between melphalan and bortezomib resistant cells, however, the bromodomain inhibitor, CPI203, was observed to have enhanced activity in both the bortezomib and melphalan resistant lines compared to their wild-type counterparts. The combination of bortezomib and CPI203 was found to be synergistic in both the bortezomib and melphalan resistant cell lines as well as in a primary multiple myeloma sample from a patient refractory to recent proteasome inhibitor treatment. The CPI203-bortezomib combination led to enhanced apoptosis and anti-proliferative effects. Finally, in contrast to prior reports of synergy between bortezomib and other epigenetic modifying agents, which implicated MYC downregulation or NOXA induction, our analyses suggest that CPI203-bortezomib synergy is independent of these events.

Conclusion

Our preclinical data supports a role for the clinical investigation of the bromodomain inhibitor CPI203 combined with bortezomib or alkylating agents in resistant multiple myeloma.

Nivolumab in Patients With Relapsed or Refractory Hematologic Malignancy: Preliminary Results of a Phase Ib Study

PURPOSE

Cancer cells can exploit the programmed death-1 (PD-1) immune checkpoint pathway to avoid immune surveillance by modulating T-lymphocyte activity. In part, this may occur through overexpression of PD-1 and PD-1 pathway ligands (PD-L1 and PD-L2) in the tumor microenvironment. PD-1 blockade has produced significant antitumor activity in solid tumors, and similar evidence has emerged in hematologic malignancies.

METHODS

In this phase I, open-label, dose-escalation, cohort-expansion study, patients with relapsed or refractory B-cell lymphoma, T-cell lymphoma, and multiple myeloma received the anti-PD-1 monoclonal antibody nivolumab at doses of 1 or 3 mg/kg every 2 weeks. This study aimed to evaluate the safety and efficacy of nivolumab and to assess PD-L1/PD-L2 locus integrity and protein expression.

RESULTS

Eighty-one patients were treated (follicular lymphoma, n = 10; diffuse large B-cell lymphoma, n = 11; other B-cell lymphomas, n = 10; mycosis fungoides, n = 13; peripheral T-cell lymphoma, n = 5; other T-cell lymphomas, n = 5; multiple myeloma, n = 27). Patients had received a median of three (range, one to 12) prior systemic treatments. Drug-related adverse events occurred in 51 (63%) patients, and most were grade 1 or 2. Objective response rates were 40%, 36%, 15%, and 40% among patients with follicular lymphoma, diffuse large B-cell lymphoma, mycosis fungoides, and peripheral T-cell lymphoma, respectively. Median time of follow-up observation was 66.6 weeks (range, 1.6 to 132.0+ weeks). Durations of response in individual patients ranged from 6.0 to 81.6+ weeks.

CONCLUSION

Nivolumab was well tolerated and exhibited antitumor activity in extensively pretreated patients with relapsed or refractory B- and T-cell lymphomas. Additional studies of nivolumab in these diseases are ongoing.

A hot L1 retrotransposon evades somatic repression and initiates human colorectal cancer

Although human LINE-1 (L1) elements are actively mobilized in many cancers, a role for somatic L1 retrotransposition in tumor initiation has not been conclusively demonstrated. Here, we identify a novel somatic L1 insertion in the APC tumor suppressor gene that provided us with a unique opportunity to determine whether such insertions can actually initiate colorectal cancer (CRC), and if so, how this might occur. Our data support a model whereby a hot L1 source element on Chromosome 17 of the patient's genome evaded somatic repression in normal colon tissues and thereby initiated CRC by mutating the APC gene. This insertion worked together with a point mutation in the second APC allele to initiate tumorigenesis through the classic two-hit CRC pathway. We also show that L1 source profiles vary considerably depending on the ancestry of an individual, and that population-specific hot L1 elements represent a novel form of cancer risk.

Daratumumab monotherapy in patients with treatment-refractory multiple myeloma (SIRIUS): an open-label, randomised, phase 2 trial

BACKGROUND

New treatment options are needed for patients with multiple myeloma that is refractory to proteasome inhibitors and immunomodulatory drugs. We assessed daratumumab, a novel CD38-targeted monoclonal antibody, in patients with refractory multiple myeloma.

METHODS

In this open-label, multicentre, phase 2 trial done in Canada, Spain, and the USA, patients (age ≥18 years) with multiple myeloma who were previously treated with at least three lines of therapy (including proteasome inhibitors and immunomodulatory drugs), or were refractory to both proteasome inhibitors and immunomodulatory drugs, were randomly allocated in a 1:1 ratio to receive intravenous daratumumab 8 mg/kg or 16 mg/kg in part 1 stage 1 of the study, to decide the dose for further assessment in part 2. Patients received 8 mg/kg every 4 weeks, or 16 mg/kg per week for 8 weeks (cycles 1 and 2), then every 2 weeks for 16 weeks (cycles 3-6), and then every 4 weeks thereafter (cycle 7 and higher). The allocation schedule was computer-generated and randomisation, with permuted blocks, was done centrally with an interactive web response system. In part 1 stage 2 and part 2, patients received 16 mg/kg dosed as in part 1 stage 1. The primary endpoint was overall response rate (partial response [PR] + very good PR + complete response [CR] + stringent CR). All patients who received at least one dose of daratumumab were included in the analysis. The trial is registered with ClinicalTrials.gov, number NCT01985126.

FINDINGS

The study is ongoing. In part 1 stage 1 of the study, 18 patients were randomly allocated to the 8 mg/kg group and 16 to the 16 mg/kg group. Findings are reported for the 106 patients who received daratumumab 16 mg/kg in parts 1 and 2. Patients received a median of five previous lines of therapy (range 2-14). 85 (80%) patients had previously received autologous stem cell transplantation, 101 (95%) were refractory to the most recent proteasome inhibitors and immunomodulatory drugs used, and 103 (97%) were refractory to the last line of therapy. Overall responses were noted in 31 patients (29.2%, 95% CI 20.8-38.9)-three (2.8%, 0.6-8.0) had a stringent CR, ten (9.4%, 4.6-16.7) had a very good PR, and 18 (17.0%, 10.4-25.5) had a PR. The median time to first response was 1.0 month (range 0.9-5.6). Median duration of response was 7.4 months (95% CI 5.5-not estimable) and progression-free survival was 3.7 months (95% CI 2.8-4.6). The 12-month overall survival was 64.8% (95% CI 51.2-75.5) and, at a subsequent cutoff, median overall survival was 17.5 months (95% CI 13.7-not estimable). Daratumumab was well tolerated; fatigue (42 [40%] patients) and anaemia (35 [33%]) of any grade were the most common adverse events. No drug-related adverse events led to treatment discontinuation.

INTERPRETATION

Daratumumab monotherapy showed encouraging efficacy in heavily pretreated and refractory patients with multiple myeloma, with a favourable safety profile in this population of patients.

FUNDING

Janssen Research & Development.

Improved Outcomes After Autologous Hematopoietic Cell Transplantation for Light Chain Amyloidosis: A Center for International Blood and Marrow Transplant Research Study

PURPOSE

Autologous hematopoietic cell transplantation, or autotransplantation, is effective in light-chain amyloidosis (AL), but it is associated with a high risk of early mortality (EM). In a multicenter randomized comparison against oral chemotherapy, autotransplantation was associated with 24% EM. We analyzed trends in outcomes after autologous hematopoietic cell transplantation for AL in North America.

PATIENTS AND METHODS

Between 1995 and 2012, 1,536 patients with AL who underwent autotransplantation at 134 centers were identified in the Center for International Blood and Marrow Transplant Research database. EM and overall survival (OS) were analyzed in three time cohorts: 1995 to 2000 (n = 140), 2001 to 2006 (n = 596), and 2007 to 2012 (n = 800). Hematologic and renal responses and factors associated with EM, relapse and/or progression, progression-free survival and OS were analyzed in more recent subgroups from 2001 to 2006 (n = 197) and from 2007 to 2012 (n = 157).

RESULTS

Mortality at 30 and 100 days progressively declined over successive time periods from 11% and 20%, respectively, in 1995 to 2000 to 5% and 11%, respectively, in 2001 to 2006, and to 3% and 5%, respectively, in 2007 to 2012. Correspondingly, 5-year OS improved from 55% in 1995 to 2000 to 61% in 2001 to 2006 and to 77% in 2007 to 2012. Hematologic response to transplantation improved in the latest cohort. Renal response rate was 32%. Centers performing more than four AL transplantations per year had superior survival outcomes. In the multivariable analysis, cardiac AL was associated with high EM and inferior progression-free survival and OS. Autotransplantation in 2007 to 2012 and use of higher dosages of melphalan were associated with a lowered relapse risk. A Karnofsky score less than 80 and creatinine levels 2 mg/m(2) or greater were associated with worsened OS.

CONCLUSION

Post-transplantation survival in AL has improved, with a dramatic reduction in early post-transplantation mortality and excellent 5-year survival. The risk-benefit ratio for autotransplantation has changed, and randomized comparison with nontransplantation approaches is again warranted.

PD-1 blockade with nivolumab in relapsed or refractory Hodgkin's lymphoma

BACKGROUND

Preclinical studies suggest that Reed-Sternberg cells exploit the programmed death 1 (PD-1) pathway to evade immune detection. In classic Hodgkin's lymphoma, alterations in chromosome 9p24.1 increase the abundance of the PD-1 ligands, PD-L1 and PD-L2, and promote their induction through Janus kinase (JAK)-signal transducer and activator of transcription (STAT) signaling. We hypothesized that nivolumab, a PD-1-blocking antibody, could inhibit tumor immune evasion in patients with relapsed or refractory Hodgkin's lymphoma.

METHODS

In this ongoing study, 23 patients with relapsed or refractory Hodgkin's lymphoma that had already been heavily treated received nivolumab (at a dose of 3 mg per kilogram of body weight) every 2 weeks until they had a complete response, tumor progression, or excessive toxic effects. Study objectives were measurement of safety and efficacy and assessment of the PDL1 and PDL2 (also called CD274 and PDCD1LG2, respectively) loci and PD-L1 and PD-L2 protein expression.

RESULTS

Of the 23 study patients, 78% were enrolled in the study after a relapse following autologous stem-cell transplantation and 78% after a relapse following the receipt of brentuximab vedotin. Drug-related adverse events of any grade and of grade 3 occurred in 78% and 22% of patients, respectively. An objective response was reported in 20 patients (87%), including 17% with a complete response and 70% with a partial response; the remaining 3 patients (13%) had stable disease. The rate of progression-free survival at 24 weeks was 86%; 11 patients were continuing to participate in the study. Reasons for discontinuation included stem-cell transplantation (in 6 patients), disease progression (in 4 patients), and drug toxicity (in 2 patients). Analyses of pretreatment tumor specimens from 10 patients revealed copy-number gains in PDL1 and PDL2 and increased expression of these ligands. Reed-Sternberg cells showed nuclear positivity of phosphorylated STAT3, indicative of active JAK-STAT signaling.

CONCLUSIONS

Nivolumab had substantial therapeutic activity and an acceptable safety profile in patients with previously heavily treated relapsed or refractory Hodgkin's lymphoma. (Funded by Bristol-Myers Squibb and others; ClinicalTrials.gov number, NCT01592370.).

Combined autophagy and proteasome inhibition: a phase 1 trial of hydroxychloroquine and bortezomib in patients with relapsed/refractory myeloma

The efficacy of proteasome inhibition for myeloma is limited by therapeutic resistance, which may be mediated by activation of the autophagy pathway as an alternative mechanism of protein degradation. Preclinical studies demonstrate that autophagy inhibition with hydroxychloroquine augments the antimyeloma efficacy of the proteasome inhibitor bortezomib. We conducted a phase I trial combining bortezomib and hydroxychloroquine for relapsed or refractory myeloma. We enrolled 25 patients, including 11 (44%) refractory to prior bortezomib. No protocol-defined dose-limiting toxicities occurred, and we identified a recommended phase 2 dose of hydroxychloroquine 600 mg twice daily with standard doses of bortezomib, at which we observed dose-related gastrointestinal toxicity and cytopenias. Of 22 patients evaluable for response, 3 (14%) had very good partial responses, 3 (14%) had minor responses, and 10 (45%) had a period of stable disease. Electron micrographs of bone marrow plasma cells collected at baseline, after a hydroxychloroquine run-in, and after combined therapy showed therapy-associated increases in autophagic vacuoles, consistent with the combined effects of increased trafficking of misfolded proteins to autophagic vacuoles and inhibition of their degradative capacity. Combined targeting of proteasomal and autophagic protein degradation using bortezomib and hydroxychloroquine is therefore feasible and a potentially useful strategy for improving outcomes in myeloma therapy.

Partial correction of the CNS lysosomal storage defect in a mouse model of juvenile neuronal ceroid lipofuscinosis by neonatal CNS administration of an adeno-associated virus serotype rh.10 vector expressing the human CLN3 gene

Juvenile neuronal ceroid lipofuscinosis (JNCL or CLN3 disease) is an autosomal recessive lysosomal storage disease resulting from mutations in the CLN3 gene that encodes a lysosomal membrane protein. The disease primarily affects the brain with widespread intralysosomal accumulation of autofluorescent material and fibrillary gliosis, as well as the loss of specific neuronal populations. As an experimental treatment for the CNS manifestations of JNCL, we have developed a serotype rh.10 adeno-associated virus vector expressing the human CLN3 cDNA (AAVrh.10hCLN3). We hypothesized that administration of AAVrh.10hCLN3 to the Cln3(Δex7/8) knock-in mouse model of JNCL would reverse the lysosomal storage defect, as well as have a therapeutic effect on gliosis and neuron loss. Newborn Cln3(Δex7/8) mice were administered 3 × 10(10) genome copies of AAVrh.10hCLN3 to the brain, with control groups including untreated Cln3(Δex7/8) mice and wild-type littermate mice. After 18 months, CLN3 transgene expression was detected in various locations throughout the brain, particularly in the hippocampus and deep anterior cortical regions. Changes in the CNS neuronal lysosomal accumulation of storage material were assessed by immunodetection of subunit C of ATP synthase, luxol fast blue staining, and periodic acid-Schiff staining. For all parameters, Cln3(Δex7/8) mice exhibited abnormal lysosomal accumulation, but AAVrh.10hCLN3 administration resulted in significant reductions in storage material burden. There was also a significant decrease in gliosis in AAVrh.10hCLN3-treated Cln3(Δex7/8) mice, and a trend toward improved neuron counts, compared with their untreated counterparts. These data demonstrate that AAVrh.10 delivery of a wild-type cDNA to the CNS is not harmful and instead provides a partial correction of the neurological lysosomal storage defect of a disease caused by a lysosomal membrane protein, indicating that this may be an effective therapeutic strategy for JNCL and other diseases in this category.

Complete androgen insensitivity syndrome in a black South African family: a clinical and molecular investigation

OBJECTIVE

To present the first report of a clinical and molecular investigation of a black South African family with complete androgen insensitivity syndrome (CAIS).

METHODS

Biochemical and chromosomal analyses were performed. In addition, the molecular study included microsatellite analysis and DNA sequencing.

RESULTS

The index case, an unmarried 21-year-old black phenotypic female patient with primary amenorrhea, was identified in the Division of Endocrinology at a tertiary hospital affiliated with the University of the Witwatersrand. A detailed family history identified further potentially affected members (on the basis of primary amenorrhea), who were also included in the study. A total of 13 family members, including 6 affected subjects, were involved in the molecular study. All affected persons had a 46,XY karyotype, female phenotype, and hormonal profiles commensurate with their clinical diagnosis. The androgen receptor gene in an affected patient was examined for mutations by DNA sequencing. Mutation screening was extended to other family members. The genetic basis for CAIS in this large family is the missense mutation, D732Y, in exon 5 of the androgen receptor ligand-binding domain.

CONCLUSION

To our knowledge, this is the first case report of CAIS in South Africa in which molecular genetic techniques were used to substantiate the clinical diagnosis. The findings in this study have implications for genetic counseling in this family.

Contact Palm Burns in Toddlers from Glass Enclosed Fireplaces

We have seen an alarming increase in the incidence of pediatric palm burns associated with gas fireplaces. The increasing popularity of these units places more children at risk. Medical records of patients under the age of 5 years who sustained hand burns from contact with the glass enclosure of gas fireplaces from 1996 through 2002 were reviewed. Thirty-nine patients were identified, with a mean age of 12.8 months. A 15-fold increase in incidence was observed. Thirty-three patients suffered superficial second-degree burns that were treated conservatively. Twenty-one percent of children developed significant wound complications requiring intensive therapy including extension splinting or surgery. Pediatric burns resulting from palmar contact with the glass enclosures of gas fireplaces have emerged as an avoidable new danger within the home. Although most of these injuries heal with conservative treatment alone, many require surgery or other intensive management to regain acceptable function.

Metabolic drug interactions between angiogenic inhibitor, TNP-470 and anticancer agents in primary cultured hepatocytes and microsomes

The potential metabolic drug interactions between TNP-470, a potent inhibitor of angiogenesis, and several commonly used anticancer agents, such as cyclophosphamide, taxol, and minocycline, were investigated in vitro using primary cultured hepatocytes and microsomes of rhesus monkeys. After incubation of hepatocytes with 5 microM [3H]TNP-470, rapid and extensive formation of six metabolites was observed, with M-II and M-IV being the predominant metabolites. After 30 min of incubation in the presence of 250 microM cyclophosphamide, concentrations of unchanged TNP-470 and M-IV were increased with values of 1.00 +/- 0.02 and 1.49 +/- 0.01 microM compared with control values of 0.67 +/- 0.09 (p =.02), 1.39 +/- 0. 03 microM (p <.01), respectively. In contrast, the concentration of M-II was substantially decreased from 1.69 +/- 0.86 to 1.02 +/- 0.16 microM (p =.01). Combination of taxol with TNP-470 led to a 50% decrease of M-II levels (p <.01), whereas unchanged TNP-470 and M-IV levels were increased by at least 2.5-fold compared with control (p =.08 and 0.01). Exposure of cells to TNP-470 with 250 microM minocycline had no effect on TNP-470 metabolism in monkey hepatocytes. In vitro studies with isolated monkey liver microsomes confirmed these drug-drug metabolic interactions detected at the cellular level. A detailed understanding of the potential drug interactions in TNP-470 metabolism occurring with taxol or cyclophosphamide is critical to fully elucidate the potentiation of the antitumor activity observed in vivo after coadministration of these two agents with TNP-470.

A re-investigation of the thio effect at the hammerhead cleavage site

The effect of introducing a phosphorothioate at the hammerhead cleavage site was investigated using a kinetically well-characterized hammerhead. In buffers containing Mg ion, the RP-phosphorothioate isomer cleaved 2000- to 80 000-fold slower than the SPisomer or the unmodified RNA substrate. Addition of low concentrations of several thiophilic metal ions, especially Cd2+, to these reactions is sufficient to fully restore the cleavage rate of the RPsubstrate without affecting cleavage rate of the all-oxygen or SPsubstrate. Thus, a model proposing coordination of a divalent metal ion to the pro-R oxygen at the hammerhead cleavage site appears justified.

Involvement of a specific metal ion in the transition of the hammerhead ribozyme to its catalytic conformation

Previous crystallographic and biochemical studies of the hammerhead ribozyme suggest that a metal ion is ligated by the pro-Rp oxygen of phosphate 9 and by N7 of G10.1 and has a functional role in the cleavage reaction. We have tested this model by examining the cleavage properties of a hammerhead containing a unique phosphorothioate at position 9. The Rp-, but not Sp-, phosphorothioate reduces the cleavage rate by 10(3)-fold, and the rate can be fully restored by addition of low concentrations of Cd2+, a thiophilic metal ion. These results strongly suggest that this bound metal ion is critical for catalysis, despite its location approximately 20 A from the cleavage site in the crystal structure. Analysis of the concentration dependence suggests that Cd2+ binds with a Kd of 25 microM in the ground state and a Kd of 2.5 nM in the transition state. The much stronger transition state binding suggests that the P9 metal ion adopts at least one additional ligand in the transition state and that this metal ion may participate in a large scale conformational change that precedes hammerhead cleavage.

Effects of glycosylated hemoglobin on vascular responses in vitro

Vascular responses to endothelium-dependent vasodilators are greatly impaired in vivo, while isolated blood vessels from animals with diabetes mellitus demonstrate less consistent degrees of impairment. Glycation of proteins, such as hemoglobin, has been implicated in the vascular abnormalities associated with diabetes.

OBJECTIVE

The purpose of this study was to test the hypothesis that glycosylated hemoglobin is capable of reducing endothelium-dependent vasodilator responses, possibly explaining impaired dilation observed in vivo.

METHODS

To test this hypothesis, the effect of glycosylated hemoglobin (GH) on vascular responses was studied in several vascular beds, including ventricular microvessels and coronary, mesenteric, femoral, and renal arteries. Coronary arterioles were isolated and mounted between two glass pipettes in a pressurized (30 cmH2O) organ chamber. Isolated artery segments were studied using a standard isometric ring technique.

RESULTS

In ventricular microvessels, 10 nM nGH (non-GH) and GH both attenuated the relaxation to Ach. A lower concentration, 1 nM nGH or GH, did not alter dilation to Ach. In coronary, femoral, mesenteric and renal artery segments, endothelium-dependent responses were not altered by the presence of 10 or 100 nM nGH or GH.

CONCLUSION

In coronary microvessels, and coronary, femoral, mesenteric and renal arteries, GH is not responsible for the impaired endothelial function associated with diabetes mellitus.

Interspecies variability of TNP-470 metabolism, using primary monkey, rat, and dog cultured hepatocytes

The biotransformation of TNP-470 [O-(chloroacetylcarbamoyl)fumagillol; AGM 1470], a potent in vitro inhibitor of angiogenesis, was investigated in primary cultured hepatocytes isolated from different species, including monkey, dog, and rat, as well as in microsomal fractions of various monkey tissues. Previous metabolic studies by our group using human hepatocytes in primary culture demonstrated that TNP-470 was primarily metabolized to M-IV through an ester cleavage, with subsequent conversion of M-IV to M-II by microsomal epoxide hydrolase. Additional studies using monkey liver microsomes demonstrated that M-II was then glucuronidated by uridine-5'-diphosphoglucuronyl transferase, leading to the formation of M-III. Three other, as yet unidentified, metabolites, labeled M-I, M-V, and M-VI, were also detected. Similarly to findings in human hepatocytes, the predominant extracellular metabolite was M-II in all species studied. Minor interspecies variability was observed in the total amount of drug biotransformed by hepatocytes, but some variability was detected in the metabolic pattern of TNP-470 in monkey hepatocytes, compared with rat or dog hepatocytes. In monkey hepatocytes, as previously observed in human cells, TNP-470 was metabolized to six derivatives, labeled M-I, M-II, M-III, M-IV, M-V, and M-VI, whereas the latter metabolite was not observed in dog or rat extracellular medium. Extrahepatic metabolism of TNP-470 was also studied using monkey intestine, kidney, and lung microsomes, which demonstrated that, under these experimental conditions, TNP-470 was extensively metabolized to four derivatives, i.e. M-I, M-II, M-III, and M-IV, with M-III being detected only in liver samples. These studies suggest that the metabolism of TNP-470 in monkeys appears to be most closely related to that observed in humans. Although the individual quantitative metabolic profiles were quite different in various animal species, only one metabolite, namely M-VI, was not detected in either dog or rat hepatocytes in vitro.

Estimation of total water and fatness from weight and height: inaccurate for lean women

Mellits and Cheek have provided a regression equation which predicts total water, and by extension, fat, from weight and height of women. The equation has been used by many researchers as a convenient means to estimate fat when more complicated body composition estimation techniques are not possible. It is an essential component of evidence provide by Frisch for the critical fat hypothesis. The equation has not been validated on another sample, however, and has a large standard error. I test the Mellits and Cheek equation on five samples of young women, two of which show a normal range of heights and weights. The other three are athletic samples composed of lean women. In the normal samples mean fat percent determined by density (from underwater weighing) is closely approximated by the weight and height equation but not in the lean samples. When measured fat is regressed on estimated fat, correlations are low, and standard errors are high, suggesting that the Mellits and Cheek equation predicts poorly the body fat percentage of individual females. In summary, the Mellits and Cheek equation is moderately useful for the prediction of group means for body composition on samples with normal ranges of height and weight. It does not produce acceptable results on groups selected for extreme leanness or obesity. It is not recommended for fat prediction of individuals.

Critical fat, menarche, and the maintenance of menstrual cycles: a critical review

The critical weight (fat) hypothesis has generated interest as a mechanism for the onset and maintenance of normal reproductive cycles in human females. It postulates that menarche is triggered by the attainment of a critical percentage fat and that the maintenance of menstrual cycles requires the persistence of a minimal level; each level is argued to be universal for a particular population or race and, by implication, for the species as a whole. However, an examination of the evidence reveals the hypothesis to have a number of serious methodological and empirical shortcomings which may be grouped under three headings. First, there are no acceptable measures of body fatness, and workers rely instead on estimates from height and weight which have been shown to be intolerably erroneous for individuals. Second, using either these estimates, or more reliable ones using appropriate methods, it may be shown that critical levels do not apply: numerous exceptions involving fat levels above and below the suggested threshold may be shown. Finally, where specific conditions involving reduced fatness and menstrual delay or dysfunction are used to support the hypothesis, it may be shown that other confounding factors are equally plausible. Consequently, based on available evidence, the critical weight (fat) hypothesis cannot be accepted. Hypotheses based on normal maturational processes, especially of the central nervous system, currently provide better explanations.

Increase of tooth size in prehistoric coastal Peru, 10,000 B.P.-1,000 B.P

Teeth increase in size during a 9,000-year period in an archaeologically derived, radiocarbon dated sample of skeletons from a geographically restricted area of coastal Peru. Although cultural change is extensive, including the transition to food production and pottery making, teeth do not reduce as predicted under these conditions by Brace's Probable Mutation Effect. Since most of the dental literature dealing with size change of teeth focuses upon dental reduction, hypotheses explaining why teeth increase through time are not well developed. No obvious selective forces explaining size increase are apparent in the present data. Attrition decreases through time. The increase in tooth size in this collection may be a function of overall cranialfacial size increase, which (pending further data) may be related to a general body size increase.