KRAS is vulnerable to reversible switch-II pocket engagement in cells.

Current small-molecule inhibitors of KRAS(G12C) bind irreversibly in the switch-II pocket (SII-P), exploiting the strong nucleophilicity of the acquired cysteine as well as the preponderance of the GDP-bound form of this mutant. Nevertheless, many oncogenic KRAS mutants lack these two features, and it remains unknown whether targeting the SII-P is a practical therapeutic approach for KRAS mutants beyond G12C. Here we use NMR spectroscopy and a cellular KRAS engagement assay to address this question by examining a collection of SII-P ligands from the literature and from our own laboratory. We show that the SII-Ps of many KRAS hotspot (G12, G13, Q61) mutants are accessible using noncovalent ligands, and that this accessibility is not necessarily coupled to the GDP state of KRAS. The results we describe here emphasize the SII-P as a privileged drug-binding site on KRAS and unveil new therapeutic opportunities in RAS-driven cancer.

Natural history of valve disease in patients with mucopolysaccharidosis II and the impact of enzyme replacement therapy.

Mucopolysaccharidosis II (MPS II, Hunter syndrome) is a rare, X-linked lysosomal storage disease caused by reduced activity of iduronate-2-sulfatase (I2S), with subsequent cellular accumulation of the glycosaminoglycans (GAGs), heparan sulfate, and dermatan sulfate (DS). DS is a major component of the extracellular matrix of heart valves, which can be affected in MPS II. We investigated the natural history of valve disease in MPS II and the impact of long-term intravenous enzyme replacement therapy (ERT) with recombinant I2S (idursulfase). In total, 604 cardiac examinations were assessed from serial follow-up of 80 male patients (49 neuronopathic). Valve disease was classified according to standard practice from hemodynamic features evident from echocardiography. The natural history group comprised 48 patients (up to 14.8 years of follow-up; median, 2.6 years; 24 patients started ERT during the study); 56 patients were treated (up to 14.2 years of follow-up; median, 6.2 years). Lifetime GAG burden (calculated from urinary GAG measurements) correlated significantly with the degree of valve disease. Onset of moderate-to-severe valve disease was significantly delayed in treated (median age at onset, 29.1 ± 2 [95% CI: 25.2-32.9] years; Kaplan-Meier estimation) versus untreated patients (17.6 ± 1 [95% Cl: 15.8-19.4] years; p < 0.0001). Cox regression modeling found that long-term ERT reduced the probability of developing severe valve disease (χ2, 32.736; significant after 5 years of ERT). Overall, this study found that valve disease severity in MPS II correlates with GAG burden and that progression is delayed by long-term ERT.

Comparative assessment of physics-based in silico methods to calculate relative solubilities.

Relative solubilities, i.e. whether a given molecule is more soluble in one solvent compared to others, is a critical parameter for pharmaceutical and agricultural formulation development and chemical synthesis, material science, and environmental chemistry. In silico predictions of this crucial variable can help reducing experiments, waste of solvents and synthesis optimization. In this study, we evaluate the performance of different physics-based methods for predicting relative solubilities. Our assessment involves quantum mechanics-based COSMO-RS and molecular dynamics-based free energy methods using OPLS4, the open-source OpenFF Sage, and GAFF force fields, spanning over 200 solvent-solute combinations. Our investigation highlights the important role of compound multimerization, an effect which must be accounted for to obtain accurate relative solubility predictions. The performance landscape of these methods is varied, with significant differences in precision depending on both the method used and the solute considered, thereby offering an improved understanding of the predictive power of physics-based methods in chemical research.

[Thyroid nodules as an incidental finding : Value of sonography and scintigraphy in primary diagnostics]. / Zufallsbefund Schilddrüsenknoten : Stellenwert der Sonographie und Szintigraphie in der Primärdiagnostik.

Due to the widespread use of high-resolution sonography, numerous thyroid nodules are diagnosed, often as incidental findings. The challenge lies in evaluating various criteria such as size, shape, and echogenicity to assess the nodules' malignancy risk. Risk stratification systems have been developed to enable systematic assessment as well as to avoid unnecessary medical interventions and malignant findings being overlooked. This article provides an overview of the current diagnostic standards in primary assessment of thyroid nodules.

Development of Cell Permeable NanoBRET Probes for the Measurement of PLK1 Target Engagement in Live Cells.

PLK1 is a protein kinase that regulates mitosis and is both an important oncology drug target and a potential antitarget of drugs for the DNA damage response pathway or anti-infective host kinases. To expand the range of live cell NanoBRET target engagement assays to include PLK1, we developed an energy transfer probe based on the anilino-tetrahydropteridine chemotype found in several selective PLK inhibitors. Probe 11 was used to configure NanoBRET target engagement assays for PLK1, PLK2, and PLK3 and measure the potency of several known PLK inhibitors. In-cell target engagement for PLK1 was in good agreement with the reported cellular potency for the inhibition of cell proliferation. Probe 11 enabled the investigation of the promiscuity of adavosertib, which had been described as a dual PLK1/WEE1 inhibitor in biochemical assays. Live cell target engagement analysis of adavosertib via NanoBRET demonstrated PLK activity at micromolar concentrations but only selective engagement of WEE1 at clinically relevant doses.

Carbonate-Based Fluorescent Chemical Tool for Uncovering Carboxylesterase 1 (CES1) Activity Variations in Live Cells.

Carboxylesterase 1 (CES1) plays a key role in the metabolism of endogenous biomolecules and xenobiotics including a variety of pharmaceuticals. Despite the established importance of CES1 in drug metabolism, methods to study factors that can vary CES1 activity are limited with only a few suitable for use in live cells. Herein, we report the development of FCP1, a new CES1 specific fluorescent probe with a unique carbonate substrate constructed from commercially available reagents. We show that FCP-1 can specifically report on endogenous CES1 activity with a robust fluorescence response in live HepG2 cells through studies with inhibitors and genetic knockdowns. Subsequently, we deployed FCP-1 to develop a live cell fluorescence microscopy-based approach to identify activity differences between CES1 isoforms. To the best of our knowledge, this is the first application of a fluorescent probe to measure the activity of CES1 sequence variants in live cells.

Quantitative longitudinal natural history of 8 gangliosidoses-conceptual framework and baseline data of the German 8-in-1 disease registry. A cross-sectional analysis.

PURPOSE: Gangliosidoses are a group of inherited neurogenetic autosomal recessive lysosomal storage disorders usually presenting with progressive macrocephaly, developmental delay, and regression, leading to significant morbidity and premature death. A quantitative definition of the natural history would support and enable clinical development of specific therapies. METHODS: Single disease registry of 8 gangliosidoses (NCT04624789). Cross-sectional analysis of baseline data in N = 26 patients. Primary end point: disease severity assessed by the 8-in-1 score. Secondary end points: first neurologic sign or symptom observed (1) by parents and (2) by physicians, diagnostic delay, as well as phenotypical characterization. Tertiary end points: neurologic outcomes (development, ataxia, dexterity) and disability. RESULTS: The 8-in-1 score quantitatively captured severity of disease. Parents recognized initial manifestations (startle reactions) earlier than physicians (motor developmental delay and hypotonia). Median diagnostic delay was 3.16 (interquartile range 0.69-6.25) years. In total, 8 patients presented with late-infantile phenotypes. CONCLUSION: Data in this registry raise awareness of these rare and fatal conditions to accelerate diagnosis, inform counseling of afflicted families, define quantitative end points for clinical trials, and can serve as historical controls for future therapeutic studies. We provide further insight into the rare late-infantile phenotype for GM2-gangliosidosis. Longitudinal follow up is planned.

Hepatocyte expressed chemerin-156 does not protect from experimental non-alcoholic steatohepatitis.

Non-alcoholic steatohepatitis (NASH) is a rapidly growing liver disease. The chemoattractant chemerin is abundant in hepatocytes, and hepatocyte expressed prochemerin protected from NASH. Prochemerin is inactive and different active isoforms have been described. Here, the effect of hepatocyte expressed muChem-156, a highly active murine chemerin isoform, was studied in the methionine-choline deficient dietary model of NASH. Mice overexpressing muChem-156 had higher hepatic chemerin protein. Serum chemerin levels and the capability of serum to activate the chemerin receptors was unchanged showing that the liver did not release active chemerin. Notably, activation of the chemerin receptors by hepatic vein blood did not increase in parallel to total chemerin protein in patients with liver cirrhosis. In experimental NASH, muChem-156 had no effect on liver lipids. Accordingly, overexpression of active chemerin in hepatocytes or treatment of hepatocytes with recombinant chemerin did not affect cellular triglyceride and cholesterol levels. Importantly, overexpression of muChem-156 in the murine liver did not change the hepatic expression of inflammatory and profibrotic genes. The downstream targets of chemerin such as p38 kinase were neither activated in the liver of muChem-156 producing mice nor in HepG2, Huh7 and Hepa1-6 cells overexpressing this isoform. Recombinant chemerin had no effect on global gene expression of primary human hepatocytes and hepatic stellate cells within 24 h of incubation. Phosphorylation of p38 kinase was, however, increased upon short-time incubation of HepG2 cells with chemerin. These findings show that muChem-156 overexpression in hepatocytes does not protect from liver steatosis and inflammation.

Unraveling individual host-guest interactions in molecular recognition from first principles quantum mechanics: Insights into the nature of nicotinic acetylcholine receptor agonist binding.

Drug binding to a protein target is governed by a complex pattern of noncovalent interactions between the ligand and the residues in the protein's binding pocket. Here we introduce a generally applicable, parameter-free, computational method that allows for the identification, quantification, and analysis of the key ligand-residue interactions responsible for molecular recognition. Our strategy relies on Local Energy Decomposition analysis at the "gold-standard" coupled cluster DLPNO-CCSD(T) level. In the study case shown in this paper, nicotine and imidacloprid binding to the nicotinic acetylcholine receptor, our approach provides new insights into how individual amino acids in the active site determine sensitivity and selectivity of the ligands, extending and refining classical pharmacophore hypotheses. By inference, the method is applicable to any kind of host/guest interactions with potential applications in industrial biocatalysis and protein engineering.

Clinical outcomes in patients with Philadelphia chromosome-positive leukemia treated with ponatinib in routine clinical practice-data from a Belgian registry.

Data on clinical use of ponatinib are limited. This prospective registry aimed to evaluate outcomes of ponatinib treatment in routine practice over 3 years (2016-2019) in Belgium (NCT03678454). Patients with chronic myeloid leukemia (CML) or Philadelphia chromosome-positive (Ph+) acute lymphoblastic leukemia (ALL) were treated with ponatinib per current label. Fifty patients (33 CML and 17 Ph+ ALL) were enrolled. Fifty-five percent of CML and 29% of Ph+ ALL patients had received ≥3 prior tyrosine kinase inhibitors (TKIs). Reasons for starting ponatinib were intolerance (40%), relapse or refractoriness (28%) to previous TKIs, progression (16%), or T315I mutation (16%). Median follow-up was 15 months for CML and 4.5 months for Ph+ ALL patients. Best response was a major molecular response in 58% of CML and 41% of Ph+ ALL patients. Of 20 patients who started ponatinib due to intolerance to previous TKIs, 9 (64%) CML and 4 (67%) Ph+ ALL achieved a major molecular response. Three-year estimates of overall survival were 85.3% and 85.6%, respectively, in CML and Ph+ ALL patients; estimated progression-free survival was 81.6% and 48.9%. Adverse reactions were reported in 34 patients (68%); rash (26%) and dry skin (10%) were most common. Reported cardiovascular adverse reactions included vascular stenosis (3), arterial hypertension (2), chest pain (1), palpitations (1), and vascular occlusion (1). This Belgian registry confirms results from the PACE clinical trial and supports routine ponatinib use in CML and Ph+ ALL patients who are resistant or intolerant to previous TKIs or with the T315I mutation.

A binding mode hypothesis for prothioconazole binding to CYP51 derived from first principles quantum chemistry.

In order to assess safety and efficacy of small molecule drugs as well as agrochemicals, it is key to understanding the nature of protein-ligand interaction on an atomistic level. Prothioconazole (PTZ), although commonly considered to be an azole-like inhibitor of sterol 14-α demethylase (CYP51), differs from classical azoles with respect to how it binds its target. The available evidence is only indirect, as crystallographic elucidation of CYP51 complexed with PTZ have not yet been successful. We derive a binding mode hypothesis for PTZ binding its target, compare to DPZ, a triazole-type metabolite of PTZ, and set our findings into context of its biochemistry and spectroscopy. Quantum Theory of Atoms in Molecules (QTAIM) analysis of computed DFT electron densities is used to qualitatively understand the topology of binding, revealing significant differences of how R- and S-enantiomers are binding and, in particular, how the thiozolinthione head of PTZ binds to heme compared to DPZ's triazole head. The difference of binding enthalpy is calculated at coupled cluster (DLPNO-CCSD(T)) level of theory, and we find that DPZ binds stronger to CYP51 than PTZ by more than ΔH ~ 11 kcal/mol.

Quasistatic Solutions versus Full-Wave Solutions of Single-Channel Circular RF Receive Coils on Phantoms of Varying Conductivities at 3 Tesla.

PURPOSE: Although full-wave simulations could be used to aid in RF coil design, the algorithms may be too slow for an iterative optimization algorithm. If quasistatic simulations are accurate within the design tolerance, then their use could reduce simulation time by orders of magnitude compared to full-wave simulations. This paper examines the accuracy of quasistatic and full-wave simulations at 3 Tesla. METHODS: Three sets of eight coils ranging from 3-10 cm (24 total) were used to measure SNR on three phantoms with conductivities of 0.3, 0.6, and 0.9 S/m. The phantom conductivities were chosen to represent those typically found in human tissues. The range of coil element sizes represents the sizes of coil elements seen in typical coil designs. SNR was determined using the magnetic and electric fields calculated by quasistatic and full-wave simulations. Each simulated SNR dataset was scaled to minimize the root mean squared error (RMSE) when compared against measured SNR data. In addition, the noise values calculated by each simulation were compared against benchtop measured noise values. RESULTS: The RMSE was 0.285 and 0.087 for the quasistatic and full-wave simulations, respectively. The maximum and minimum quotient values, when taking the ratio of simulated to measured SNR values, were 1.69 and 0.20 for the quasistatic simulations and 1.29 and 0.75 for the full-wave simulations, respectively. The ratio ranges, for the calculated quasistatic and full-wave total noise values compared to benchtop measured noise values, were 0.83-1.06 and 0.27-3.02, respectively. CONCLUSIONS: Full-wave simulations were on average 3x more accurate than the quasistatic simulations. Full-wave simulations were more accurate in characterizing the wave effects within the sample, though they were not able to fully account for the skin effect when calculating coil noise.

Capacitive versus Overlap Decoupling of Adjacent Radio Frequency Phased Array Coil Elements: An Imaging Robustness Comparison When Sample Load Varies for 3 Tesla MRI.

Phased array (PA) receive coils are built such that coil elements approximate independent antenna behavior. One method of achieving this goal is to use an available decoupling method to decouple adjacent coil elements. The purpose of this work was to compare the relative performance of two decoupling methods as a function of variation in sample load. Two PA receive coils with 5 channels (5-ch) each, equal outer dimensions, and formed on 12 cm diameter cylindrical phantoms of conductivities 0.3, 0.6, and 0.9 S/m were evaluated for relative signal-to-noise ratio (SNR) and parallel imaging performance. They were only tuned and matched to the 0.6 S/m phantom. Simulated and measured axial, sagittal, and coronal 5-ch PA coil SNR ratios were compared by dividing the overlap by the capacitive decoupled coil SNR results. Issues related to the selection of capacitor values for the two decoupling methods were evaluated by taking the ratio of the match and tune capacitors for large and small 2 channel (2-ch) PA coils. The SNR ratios showed that the SNR of the two decoupling methods were very similar. The inverse geometry-factor maps showed similar but better overall parallel imaging performance for the capacitive decoupled method. The quotients for the 2-ch PA coils' maximum and minimum capacitor value ratios are 3.28 and 1.38 for the large and 3.28 and 2.22 for the small PA. The results of this paper demonstrate that as the sample load varies, the capacitive and overlap decoupling methods are very similar in relative SNR and this similarity continues for parallel imaging performance. Although, for the 5-ch coils studied, the capacitive decoupling method has a slight SNR and parallel imaging advantage and it was noted that the capacitive decoupled coil is more likely to encounter unbuildable PA coil configurations.

Lysosomal alpha-galactosidase controls the generation of self lipid antigens for natural killer T cells.

Natural Killer T (NKT) cells are lipid-reactive, CD1d-restricted T lymphocytes important in infection, cancer, and autoimmunity. In addition to foreign antigens, NKT cells react with endogenous self lipids. However, in the face of stimulating self antigen, it remains unclear how overstimulation of NKT cells is avoided. We hypothesized that constantly degraded endogenous antigen only accumulates upon inhibition of alpha-galactosidase A (alpha-Gal-A) in lysosomes. Here, we show that alpha-Gal-A deficiency caused vigorous activation of NKT cells. Moreover, microbes induced inhibition of alpha-Gal-A activity in antigen-presenting cells. This temporary enzyme block depended on Toll-like receptor (TLR) signaling and ultimately triggered lysosomal lipid accumulation. Thus, we present TLR-dependent negative regulation of alpha-Gal-A as a mechanistic link between pathogen recognition and self lipid antigen induction for NKT cells.

HDAC5 Expression in Urothelial Carcinoma Cell Lines Inhibits Long-Term Proliferation but Can Promote Epithelial-to-Mesenchymal Transition.

Class I histone deacetylases (HDACs) generally promote cell proliferation and tumorigenesis, whereas class IIA HDACs like HDAC4 and HDAC5 may promote or impede cancer development in a tissue-dependent manner. In urothelial carcinoma (UC), HDAC5 is often downregulated. Accordingly, HDAC5 was weakly expressed in UC cell lines suggesting a possible tumor-suppressive function. We therefore characterized the effects of stable HDAC5 expression in four UC cell lines (RT112, VM-Cub-1, SW1710 and UM-UC-3) with different phenotypes reflecting the heterogeneity of UC, by assessing proliferation, clonogenicity and migration ability. Further, we detailed changes in the proteome and transcriptome by immunoblotting, mass spectrometry and RNA sequencing analysis. We observed that HDAC5 overexpression in general decreased cell proliferation, but in one cell line (VM-Cub-1) induced a dramatic change from an epitheloid to a mesenchymal phenotype, i.e., epithelial-mesenchymal transition (EMT). These phenotypical changes were confirmed by comprehensive proteomics and transcriptomics analyses. In contrast to HDAC5, overexpression of HDAC4 exerted only weak effects on cell proliferation and phenotypes. We conclude that overexpression of HDAC5 may generally decrease proliferation in UC, but, intriguingly, may induce EMT on its own in certain circumstances.

A Fluorescent Probe with Improved Water Solubility Permits the Analysis of Protein S-Depalmitoylation Activity in Live Cells.

S-Palmitoylation is an abundant lipid post-translational modification that is dynamically installed on and removed from target proteins to regulate their activity and cellular localization. A dearth of tools for studying the activities and regulation of protein S-depalmitoylases, thioesterase "erasers" of protein cysteine S-palmitoylation, has contributed to an incomplete understanding of the role of dynamic S-palmitoylation in regulating proteome lipidation. Recently, we developed "depalmitoylation probes" (DPPs), small molecule probes that become fluorescent upon S-depalmitoylase enzymatic activity. To be suitable for application in live cells, the first-generation DPPs relied on a shorter lipid substrate (C8 vs naturally occurring C16), which enhanced solubility and cell permeability. However, the use of an unnatural lipid substrate on the probes potentially limits the utility of the approach. Herein, we present a new member of the DPP family, DPP-5, which features an anionic carboxylate functional group that increases the probe water solubility. The enhanced water solubility of DPP-5 permits the use of a natural, palmitoylated substrate (C16), rather than a surrogate lipid. We show that DPP-5 is capable of monitoring endogenous S-depalmitoylases in live mammalian cells and that it can reveal changes in S-depalmitoylation levels due to lipid stress. DPP-5 should prove to be a useful new tool for probing the regulation of proteome lipidation through dynamic S-depalmitoylation.

99m Tc-MIP-1404-SPECT/CT for the detection of PSMA-positive lesions in 225 patients with biochemical recurrence of prostate cancer.

BACKGROUND: 99m Tc-MIP-1404 (Progenics Pharmaceuticals, Inc., New York, NY) is a novel, SPECT-compatible 99m Tc-labeled PSMA inhibitor for the detection of prostate cancer. We present results of its clinical use in a cohort of 225 men with histologically confirmed prostate cancer referred for workup of biochemical relapse. METHODS: From April 2013 to April 2017, 99m Tc-MIP1404-scintigraphy was performed in 225 patients for workup of PSA biochemical relapse of prostate cancer. Whole-body planar and SPECT/CT images of the lower abdomen and thorax were obtained 3-4 h p.i. of 710 ± 64 MBq 99m Tc-MIP-1404. Images were visually analyzed for presence and location of abnormal uptake. In addition, quantitative analysis of the SPECT/CT data was carried out on a subset of 125 patients. Follow-up reports of subsequent therapeutic interventions were available for 59% (139) of all patients. RESULTS: Tracer-positive lesions were detected in 77% (174/225) of all patients. Detections occurred at the area of local recurrence in the prostate in 25% of patients (or a total of 56), with metastases in lymph nodes in 47% (105), bone in 27% (60), lung in 5% (12), and other locations in 2% (4) of patients. Detection rates were 90% at PSA levels ≥2 ng/mL and 54% below that threshold. Lesional SUVmax values were, on average, 32.2 ± 29.6 (0.8-142.2), and tumor-to-normal ratios 146.6 ± 160.5 (1.9-1482.4). The PSA level correlated significantly with total uptake of MIP-1404 in tumors (P < 0.001). Furthermore, total tumor uptake was significantly higher in patients with Gleason scores ≥8 compared to those with Gleason scores ≤7 (P < 0.05). In patients with androgen deprivation therapy, the detection rate was significantly higher compared to patients without androgen deprivation therapy (86% vs 71%, P < 0.001). Based on 99m Tc-MIP-1404-imaging and other information, an interdisciplinary tumor board review recommended changes to treatment plans in 74% (104/139) of those patients for whom the necessary documentation was available. CONCLUSION: SPECT/CT with 99m Tc-labeled MIP-1404 has a high probability in detecting PSMA-positive lesions in patients with elevated PSA. Statistical analysis disclosed significant relationship between quantitative 99m Tc-MIP-1404 uptake, PSA level, and Gleason score.

Propofol for Treatment-Resistant Depression: A Pilot Study.

Background: We hypothesized that propofol, a unique general anesthetic that engages N-methyl-D-aspartate and gamma-aminobutyric acid receptors, has antidepressant properties. This open-label trial was designed to collect preliminary data regarding the feasibility, tolerability, and efficacy of deep propofol anesthesia for treatment-resistant depression. Methods: Ten participants with moderate-to-severe medication-resistant depression (age 18-45 years and otherwise healthy) each received a series of 10 propofol infusions. Propofol was dosed to strongly suppress electroencephalographic activity for 15 minutes. The primary depression outcome was the 24-item Hamilton Depression Rating Scale. Self-rated depression scores were compared with a group of 20 patients who received electroconvulsive therapy. Results: Propofol treatments were well tolerated by all subjects. No serious adverse events occurred. Montreal Cognitive Assessment scores remained stable. Hamilton scores decreased by a mean of 20 points (range 0-45 points), corresponding to a mean 58% improvement from baseline (range 0-100%). Six of the 10 subjects met the criteria for response (>50% improvement). Self-rated depression improved similarly in the propofol group and electroconvulsive therapy group. Five of the 6 propofol responders remained well for at least 3 months. In posthoc analyses, electroencephalographic measures predicted clinical response to propofol. Conclusions: These findings demonstrate that high-dose propofol treatment is feasible and well tolerated by individuals with treatment-resistant depression who are otherwise healthy. Propofol may trigger rapid, durable antidepressant effects similar to electroconvulsive therapy but with fewer side effects. Controlled studies are warranted to further evaluate propofol's antidepressant efficacy and mechanisms of action. ClinicalTrials.gov: NCT02935647.

68Ga-PSMA-11 PET/CT-derived metabolic parameters for determination of whole-body tumor burden and treatment response in prostate cancer.

PURPOSE: We aimed at evaluating the role of 68Ga-PSMA-11 PET/CT-derived metabolic parameters for assessment of whole-body tumor burden and its capability to determine therapeutic response in patients with prostate cancer. METHODS: A total of 142 patients with biochemical recurrence of prostate cancer underwent PET/CT with [68Ga]Ga-PSMA-HBED-CC (68Ga-PSMA-11). Quantitative assessment of all 641 68Ga-PSMA-11-positive lesions in the field of view was performed to calculate PSMA-derived parameters, including whole-body PSMA tumor volume (PSMA-TV) and whole-body total lesion PSMA (TL-PSMA), as well as the established SUVmax and SUVmean values. All PET-derived parameters were tested for correlation with serum PSA levels and for association with Gleason scores. In 23 patients who underwent 68Ga-PSMA-11 PET/CT before and after therapy with either external beam radiation, androgen deprivation, or docetaxel chemotherapy, SUVmax and TL-PSMA were compared to radiographic response assessment of CT images based on RECIST 1.1 criteria and to biochemical response determined by changes of serum PSA levels. RESULTS: PSMA-TV and TL-PSMA demonstrated a significant correlation with serum PSA levels (P < 0.0001) and TL-PSMA was significantly different for different Gleason scores. The agreement rate between TL-PSMA derived from PET and biochemical response was 87% (95% confidence interval, 0.66-0.97; Cohen's κ = 0.78; P < 0.01) and, thus, higher than for SUVmax, which was 74% (95% CI, 0.52-0.90; κ = 0.55; P < 0.01). Furthermore, agreement with PSA was higher for TL-PSMA and SUVmax than for CT-based response evaluation. Discordant findings between PET and CT were most likely due to limitations of CT and RECIST in rating small lymph nodes as metastases, as well as bone involvement, which was sometimes not detectable in CT. CONCLUSION: 68Ga-PSMA-11 PET/CT-derived metabolic tumor parameters showed promising results for evaluation of treatment response. Especially, TL-PSMA demonstrated higher agreement rates with biochemical response compared to SUVmax. Larger, ideally prospective trials are needed to help to reveal the full potential of metabolic parameters derived from PET imaging with 68Ga-PSMA-11.

Efficacy and safety of Velmanase alfa in the treatment of patients with alpha-mannosidosis: results from the core and extension phase analysis of a phase III multicentre, double-blind, randomised, placebo-controlled trial.

INTRODUCTION: This phase III, double-blind, randomised, placebo-controlled trial (and extension phase) was designed to assess the efficacy and safety of velmanase alfa (VA) in alpha-mannosidosis (AM) patients. METHODS: Twenty-five patients were randomised to weekly 1 mg/kg VA or placebo for 52 weeks. At study conclusion, placebo patients switched to VA; 23 patients continued receiving VA in compassionate-use/follow-on studies and were evaluated in the extension phase [last observation (LO)]. Co-primary endpoints were changes in serum oligosaccharide (S-oligo) and in the 3-min stair-climb test (3MSCT). RESULTS: Mean relative change in S-oligo in the VA arm was -77.6% [95% confidence interval (CI) -81.6 to -72.8] at week 52 and -62.9% (95% CI -85.8 to -40.0) at LO; mean relative change in the placebo arm was -24.1% (95% CI -40.3 to -3.6) at week 52 and -55.7% (95% CI -76.4 to -34.9) at LO after switch to active treatment. Mean relative change in 3MSCT at week 52 was -1.1% (95% CI -9.0 to 7.6) and - % (95% CI -13.4 to 6.5) for VA and placebo, respectively. At LO, the mean relative change was 3.9% (95% CI -5.5 to 13.2) in the VA arm and 9.0% (95% CI -10.3 to 28.3) in placebo patients after switch to active treatment. Similar improvement pattern was observed in secondary parameters. A post hoc analysis investigated whether some factors at baseline could account for treatment outcome; none of those factors were predictive of the response to VA, besides age. CONCLUSIONS: These findings support the utility of VA for the treatment of AM, with more evident benefit over time and when treatment is started in the paediatric age.