Comparison of clinical safety between standard versus extended interval dosing of immune checkpoint inhibitors: a real-world retrospective cohort study

BACKGROUND

Extended interval dosing (ED) for inhibitors of programmed cell death protein 1 (anti-PD-1) (nivolumab, pembrolizumab) or its ligand (anti-PD-L1) (durvalumab) were recently approved based on pharmacokinetic model results that predicted a benefit-risk profile comparable with the standard dosing (SD) regimen. However, safety data in real-world condition of use are lacking. The objective was to compare the incidence and the risk factors of serious immune-related adverse events (irAEs) and any-grade irAEs between the SD and ED regimens in patients treated with anti-PD-1 or anti-PD-L1.

MATERIALS AND METHODS

IrAEs were assessed from medical records in all new users of nivolumab, pembrolizumab, or durvalumab between 1 January 2019 and 31 December 2020 across two oncology centers in France. The incidence of irAEs was compared between both dosing regimens using Cox proportional hazards models adjusting for the main available confounders.

RESULTS

Among 686 patients included, 63% were new users of an SD regimen, 14% of ED regimen, and 23% started with SD and switched to ED regimen during follow-up. Overall, 34.6% of patients experienced at least one irAE of any grade and 11.4% presented at least one serious grade ≥3 irAE. No statistical difference was found between the SD and ED regimen on the risk of grade ≥3 irAEs [adjusted hazard ratio (HR) 1.40, 95% confidence interval (CI) 0.71-2.76] but our results suggest an increased risk of any-grade irAEs with the ED regimen (adjusted HR 1.46, 95% CI 1.00-2.12, P = 0.048). IrAEs resolved without sequelae in 46.4% of cases, and they were fatal for three patients (0.4%). Autoimmune pre-existing condition was confirmed as a risk factor for grade ≥3 irAEs (HR 2.56, 95% CI 1.53-4.27) and for all-grade irAEs (HR 1.60, 95% CI 1.17-2.20).

CONCLUSIONS

In a real-world setting, according to the regimen chosen by the oncologist based on clinical characteristics, we did not observe an increase in grade ≥3 irAE incidence between the SD and ED regimens.

Combined climate impacts and vulnerability index on coastal ecosystems in prediction of future scenarios: extended sustainable indicator tool for adaptive strategy

This study presents the coastal vulnerability due to the forecasted climate change impact on the marine environment, including the sea level rise physical trait of risk impact. A combined methodology using Representative Concentration Pathways (RCPs), which corresponds to the greenhouse gas emissions scenarios, is used in this research; combined with Climate Change Vulnerability Index (CCVI) to rank the relative risk for each of the marine ecosystem zones in relation to the potential hazard exacerbated by climate change and sea-level rise. This method presents vulnerability in numerical data, which cannot be calculated directly based on their physical properties. From the results, it shows that the coastal areas of the study area of Marudu Bay would experience a warmer atmosphere both under RCP 4.5 and RCP 8.5 with an increment of 1.0 °C and 1.7 °C; meanwhile, the climate projection for total exhibits of increase in total precipitation by 2.6 mm/day and 1.6. mm/day under RCP 4.5 and RCP 8.5 at the regional measure. At the same time, the projection simulates an increase of sea level by 0.21 m and 0.27 m over the northern region of Marudu Bay under RCP 4.5 and RCP 8.5, respectively. In addition, 43.84 ha and 57.02 ha of land estimated would be potentially inundated by the mid-century year 2050 under RCP 4.5 and RCP 8.5. By the end of the century 2100, the sea level is projected to increase locally at about 0.32 m under RCP 4.5 and 0.38 m under RCP 8.5, consequently resulting in a total of 66.84 ha and 79.78 ha of additional inundation coverage. Therefore, the result from this study can be used when making effective adaptive strategies and conservation planning despite its inherent uncertainties.

Excited States in Bilayer Graphene Quantum Dots

We report ground- and excited-state transport through an electrostatically defined few-hole quantum dot in bilayer graphene in both parallel and perpendicular applied magnetic fields. A remarkably clear level scheme for the two-particle spectra is found by analyzing finite bias spectroscopy data within a two-particle model including spin and valley degrees of freedom. We identify the two-hole ground state to be a spin-triplet and valley-singlet state. This spin alignment can be seen as Hund's rule for a valley-degenerate system, which is fundamentally different from quantum dots in carbon nanotubes, where the two-particle ground state is a spin-singlet state. The spin-singlet excited states are found to be valley-triplet states by tilting the magnetic field with respect to the sample plane. We quantify the exchange energy to be 0.35 meV and measure a valley and spin g factor of 36 and 2, respectively.

Encapsulation of oligonucleotides in stealth Me.PEG-PLA50 nanoparticles by complexation with structured oligopeptides

Two oligopeptides with alternating hydrophilic-hydrophobic amino acids, H-(leu-lys-lys-leu)10-OH and H-(leu-lys-leu-lys)10-OH, were shown to have higher affinity for a 13-mer oligonucleotide than H-(pro-lys-lys-leu)10-OH used as a control. This increased affinity was correlated to the secondary structure adopted by the oligopeptides (respectively, α-helix and β-sheet for LKKL and LK) when complexed to the oligonucleotide. Tight ion-pairing association between the phosphate groups of the oligonucleotide and the lysines of the oligopeptide led to efficient encapsulation of the resulting oligonucleotide/oligopeptide non-water-soluble complex in hydrophobic Me.PEG-PLA50 nanoparticles, by coprecipitation with the co-polymer.

Binding of heparin-dependent antibodies to PF4 modified by enoxaparin oligosaccharides: evaluation by surface plasmon resonance and serotonin release assay

BACKGROUND

The minimal structural requirements of low-molecular-weight heparins that determine the risk of developing heparin-induced thrombocytopenia (HIT) are not fully defined.

OBJECTIVES

The ability of enoxaparin-derived oligosaccharides (OS) to induce platelet activation and exposure of platelet-factor 4 (PF4) epitopes recognized by antibodies developed in HIT was studied by surface plasmon resonance (SPR) and serotonin release assay.

RESULTS

Decasaccharides with ≥ 11 sulfate groups induced platelet activation in the presence of plasma from patients with confirmed HIT. Serotonin release of > 80% without full inhibition at 100 μg mL(-1) was achieved with decasaccharides containing 14 or 15 sulfate groups, 2 dodecasaccharides and 2 tetradecasaccharides. An SPR method was developed using purified PF4 immobilized on carboxymethylated dextran. Antibodies from all HIT samples bound to PF4/heparin in SPR assays with resonance units (RU) ratio of 109-173 with HIT plasma vs. 88-93 with control plasma. RU ratios > 100 were measured when PF4 was pre-incubated with OS with ≥ 10 saccharide units and one octasaccharide containing 10 sulfate groups. RU ratios > 140, similar to those measured when PF4 was pre-incubated with unfractionated heparin or enoxaparin, were obtained with purified dodeca- and tetradecasaccharides. RU values strongly correlated with the number of sulfate groups in the decasaccharides tested (r = 0.93, P = 0.02).

CONCLUSIONS

LMWHs with fragments > 10 saccharides and a large number of sulfate groups are more likely to be associated with a higher risk of HIT. These structure-activity relationships were independent of the ability of the OS to bind antithrombin.

Chronic anal fissure: common aetiopathogenesis, with special attention to sexual abuse

BACKGROUND

Chronic anal fissures represent 15% of proctologic consultations, although their aetiopathogenesis is unclear and multifactorial. This study aims to identify the aetiopathogenesis, risk factor of recurrence after lateral subcutaneous internal anal sphincterotomy and existing correlation with sexual abuse, as sexual abuse accounts for over 21% of anal fissures.

PATIENTS AND METHODS

We retrospectively studied 80 cases of surgical (n = 54) and medical (n = 26) patients known with chronic anal fissure over eight months. We built an original questionnaire referring to the NorVold Abuse Questionnaire. Sixty cases were interviewed with only twenty filling the questionnaire themselves.

RESULTS

Among the aetiological factors observed, as reported by these patients, we underlined chronic constipation 51 (64%), postoperative haemorrhoidectomy 15 (19%), sexual abuse 15 (19%), vaginal delivery and hysterectomy 10 (13%), traumatic anal sex 10 (13%), digital anal examination 4 (5%), anti-inflammatory non-steroid suppository 3 (4%), asthma with chronic cough 3 (4%). The recurrence rate reached 39% (31 cases, 13/26 (50%) in the medical group, against 18/54 (33%) in the surgical group. The 4/15 (27%) of sexual abuse happened in adulthood and 6/15 (40%) never disclosed this information.

CONCLUSION

Sexual abuse is a significant aetiological factor of chronic anal fissures and it is to be suspected in cases of recurrence after anal sphincterotomy. For such cases, a multidisciplinary treatment is crucial to improve the prognosis of the disease. We recognise that the causality is difficult to prove and we cannot confirm that every sexually abused person could inevitably develop chronic anal fissure.

Isolation and Characterization of Contaminants in Recalled Unfractionated Heparin and Low-Molecular-Weight Heparin

Recently, a contaminant was found in some clinically used unfractionated heparin (UFH) preparations. Administration of this UFH was associated with an increased risk of developing a wide range of adverse effects including death. To further investigate the chemical profile of the contaminant, contaminated batches of UFH were treated by exhaustive nitrous acid depolymerization followed by methanol precipitation to remove heparin oligosaccharides. Because contaminated heparins may have been used as starting material in the production of low-molecular-weight heparins (LMWHs), a similar procedure was carried out using an experimental batch of enoxaparin prepared from contaminated heparin. While high-pressure liquid chromatography (HPLC) analysis of contaminated heparin did not distinguish the presence of the contaminant, it could readily be observed as a high-molecular weight shoulder in the elution profile of contaminated enoxaparin. Digesting contaminated heparin with heparinase-I prior to HPLC analysis showed the presence of a nondigestible component (15%-30% of the mixture). This contaminant was also resistant to degradation by chondroitinases A, B, and C. Proton nuclear magnetic resonance (NMR) indicated that the contaminant was oversulfated chondroitin sulfate (OSCS). Size-exclusion chromatography indicated that the mean molecular weight of the OSCS was 16.8 kD, comparable to that of a synthetic porcine cartilage OSCS preparation that was used as a reference material (17.2 kD). While varying degrees of high-molecular weight dermatan sulfate and other minor impurities were detected, OSCS appeared to be the major contaminant in these preparations. The process involved in the production of enoxaparin does not significantly degrade OSCS.

Nitrogen dynamics of a mountain forest on dolomitic limestone--a scenario-based risk assessment

The dominant nitrogen (N) fluxes were simulated in a mountain forest ecosystem on dolomitic bedrock in the Austrian Alps. Based on an existing small-scale climate model the simulation encompassed the present situation and a 50-yr projection. The investigated scenarios were current climate, current N deposition (SC1) and future climate (+2.5 degrees C and +10% annual precipitation) with three levels of N deposition (SC2, 3, 4). The microbially mediated N transformation, including the emission of nitrogen oxides, was calculated with PnET-N-DNDC. Soil hydrology was calculated with HYDRUS and was used to estimate the leaching of nitrate. The expected change of the forest ecosystem due to changes of the climate and the N availability was simulated with PICUS. The incentive for the project was the fact that forests on dolomitic limestone stock on shallow Rendzic Leptosols that are rich in soil organic matter are considered highly sensitive to the expected environmental changes. The simulation results showed a strong effect due to increased temperatures and to elevated levels of N deposition. The outflux of N, both as nitrate (6-25 kg N ha(-1)yr(-1)) and nitrogen oxides (1-2 kg N ha(-1)yr(-1)), from the forest ecosystem are expected to increase. Temperature exerts a stronger effect on the N(2)O emission than the increased rate of N deposition. The main part of the N emission will occur as N(2) (15 kg N ha(-1)yr(-1)). The total N loss is partially offset by increased rates of N uptake in the biomass due to an increase in forest productivity.

Evaluation of pollution-related stress factors for forest ecosystems in central Europe

Since the early eighties air pollution by SO2 and Pb and, to a lesser degree by NOx and NH3, have been significantly reduced in Europe. This was done in part for the protection of forest ecosystems. The reductions are reflected in the pollutant impacts and inputs and have been verified through the bioindicator Norway spruce. In contrast, ozone concentrations increased at most of the evaluated measuring locations and trends were calculated based on the results of about 100 stations in Austria and Germany. Despite reduced emissions, large parts of the forest ecosystems are still affected by air-pollution impacts. Negative effects can be assessed using different legal standards and Critical Levels and Critical Loads, respectively: The legal standard for the evaluation of SO2 impact, as used in Austria, is well suited. The provisional European Critical Level for ozone, the AOT40 must, in order to be a meaningful criterion for field applications, be further refined. Continuing the Critical Load concept, the spatial risk of acid depositions in areas of high geomorphic variability were evaluated using the new parameter of 'critical soil depth'. With the help of the newly defined 'lead accumulation index', the accumulation of Pb from air pollution could be evaluated. Air-pollution inputs and the spatial acidification risk is directly related to altitude. Up to altitudes of 1000 m and 1100 m, SO2 impact and acid depositions, respectively were indicated and elevated ozone doses and Pb inputs were observed in the sensitive sub-alpine areas. These results underline the necessity for increased protection of mountain forest ecosystems, among others through a further reduction of emissions or forest-related strategies.

Indeno[1,2-b]pyrazin-2,3-diones: a new class of antagonists at the glycine site of the NMDA receptor with potent in vivo activity

Indeno¿1,2-bpyrazin-2,3-diones have been identified as a novel series of potent ligands on the glycine site of the NMDA receptor. To improve their in vivo activities, an acetic acid-type side chain was introduced to the 5-position, giving water-soluble compounds when formulated as the sodium salt (>10 mg/mL). Introduction of a chlorine atom in the 8-position led to a dramatic improvement of anticonvulsant activity and this was surprising since this change did not improve binding affinity. A plausible explanation is a reduced recognition by a Na(+),K(+)-ATPase active transport system responsible for the excretion of these compounds from the brain and kidney. This promising new chemical series led to the optically active isomer (-)-10i (RPR 118723), a glycine/NMDA antagonist with nanomolar binding affinity and in vivo activity in animal model of convulsions and electrophysiology at doses in the range of 2-3 mg/kg following iv administration.

RPR112378 and RPR115781: two representatives of a new family of microtubule assembly inhibitors

A screening program aimed at the discovery of new antimicrotubule agents yielded RPR112378 and RPR115781, two natural compounds extracted from the Indian plant Ottelia alismoides. We report their isolation, structural determination, and mechanisms of action. RPR112378 is an efficient inhibitor of tubulin polymerization (IC(50) = 1.2 microM) and is able to disassemble preformed microtubules. Regarding tubulin activity, RPR115781 is 5-fold less active than RPR112378. Tubulin-RPR112378 complexes, when isolated by gel filtration, were able to block further tubulin addition to growing microtubules, a mechanism that accounts for the substoichiometric effect of the drug. RPR112378 was found to prevent colchicine binding but not vinblastine binding to tubulin. Although colchicine binding is known to induce an increase of tubulin GTPase activity, no such increase was observed with RPR112378. We show that RPR112378 is a highly cytotoxic compound and that RPR115781 is 10, 000-fold less active as an inhibitor of KB cell growth. Part of the cytotoxicity of RPR112378 is probably caused by a reaction of addition with sulfhydryl groups, an observation that has not been made with RPR115781. In conclusion, these molecules represent a new class of inhibitors of microtubule assembly with potential therapeutic value.

[Dysfunction of the sphincter of Oddi in cholecystectomy patients]

Sphincter of Oddi dysfunction (SOD) is an obstructive syndrome of the papilla not resulting from a stone. It may cause recurrent biliary type pain to cholecystectomized patients. SOD is caused by sphincter dyskinesia or benign stenosis. Diagnosis is usually based on symptoms, serum biochemistry, endoscopic retrograde cholangiopancreatography and Sphincter of Oddi manometry. The latter is the best means of evaluating Sphincter of Oddi dynamics. However, because of the many inconveniences of Sphincter of Oddi manometry and of its high morbidity rate, it is seldom used. Non invasive techniques, such as cholescintigraphy, have been developed to replace Sphincter of Oddi manometry in diagnosing SOD. Patients can be cured by sphincterotomy. Certain drugs could also be effective but few controlled studies have been carried out of date.

Degradation pathways of salmon calcitonin in aqueous solution

Salmon calcitonin (sCT), a 32-amino-acid peptide, is the active component in many pharmaceuticals used for the management of bone diseases. The degradation pathways of sCT were determined, and the structures of the major degradation products were identified. Aqueous solutions of sCT at pH values of 3, 4, 5, and 6 were degraded, and the major degradation products were detected using reversed phase and size-exclusion high-performance liquid chromatography (HPLC). The degradation rate and pathways of sCT are strongly dependent on pH in the pH range between 3 and 6. The major degradation products were isolated by semipreparative HPLC and identified using a variety of spectroscopic and bioanalytical techniques. The results show that sCT can undergo hydrolyses resulting in cleavage of the 1-2 amide bond and deamidation of the Gln14 and Gln20 residues, sulfide exchange that leads to an unusual trisulfide derivative, and dimerization to reducible and nonreducible dimers. The mechanisms for the pathways can be rationalized from known degradation pathways of peptide and proteins.

Solution structure of RP 71955, a new 21 amino acid tricyclic peptide active against HIV-1 virus

The structure of RP 71955, a new tricyclic 21 amino acid peptide active against human immunodeficiency virus 1, was determined. Its amino acid composition was inferred from the results of fast atom bombardment mass spectrometry, nuclear magnetic resonance, Raman spectroscopy, and amino acid analysis. Its sequence could not be determined classically, using Edman degradation, given the lack of a free terminal NH2. It was deduced from the interpretation of interresidue nuclear Overhauser effects and confirmed by the sequencing of peptides obtained by limited chemical hydrolysis. It was found to be CLGIGSCNDFAGCGYAVVCFW. An internal amide bond between the NH2 of C1 and the gamma-COOH of D9 was observed, as well as two disulfide bridges, one between C1 and C13 and one between C7 and C19. The three-dimensional structure of RP 71955 was determined from nuclear magnetic resonance derived constraints using distance geometry, restrained molecular dynamics, nuclear Overhauser effect back calculation, and an iterative refinement using a full relaxation matrix approach. Analogies between the structure of RP 71955 and some functional domains of gp41, the transmembrane protein of human immunodeficiency virus 1, suggest hypotheses concerning the mode of action of RP 71955.

A d(GpG)-platinated decanucleotide duplex is kinked. An extended NMR and molecular mechanics study

A conformational study of the double-stranded decanucleotide d(GCCG*G*ATCGC).d(GCGATCCGGC), with the G* guanines chelating a cis-Pt(NH3)2 moiety, has been accomplished using 1H and 31P NMR, and molecular mechanics. Correlation of the NMR data with molecular models has disclosed an equilibrium between several kinked conformations and has ruled out an unkinked structure. The deformation is localized at the CG*G*.CCG trinucleotide where the helix is kinked by approximately 60 degrees towards the major groove and unwound by 12-19 degrees. The models revealed an unexpected mobility of the cytosine complementary to the 5'-G*. This cytosine can stack on either branch of the kinked complementary strand. The energy barrier between the two positions has been calculated to be less than or equal to 12 kJ/mol. The NMR data are in support of rapid flip-flopping of this cytosine. An explanation for the strong downfield shift observed in the 31P resonance of the G*pG* phosphate is given.

A high melting cis-[Pt(NH3)2[d(GpG)]]adduct of a decanucleotide duplex

The [cis-Pt(NH3)2(d(GCCGGATCGC)-N7(4), N7(5))]-d(GCGATCCGGC) duplex has been prepared with Tm = 49 degrees C (vs 58 degrees C for the unplatinated form). NMR of the ten observable imino protons supports a kinked structure with intact base pairing of the duplex on the 3'-side of the d(GpG).cis-Pt chelate (relative to the platinated strand) The modification of the B-DNA type CD spectrum, due to the platinum chelate, is comparable to that observed for the platination (at a 0.05 Pt:base ratio) of the Micrococcus Lysodeikticus DNA (72% GC).

The tetraphocomelia-cleft palate syndrome in identical twins

An identical pair of twins with the tetraphocomelia-cleft palate syndrome is presented. It is hypothesized that Roberts' syndrome and the pseudothalidomide syndrome, previously reported as separate entities, represent different manifestations of the same autosomal, recessively inherited malformation pattern.

[Research on congenital Plasmodium berghei berghei malaria in mice. Transplacental passage of the parasite and its evolution]

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