Mechanism and rational combinations with GP-2250, a novel oxathiazine derivative, in ovarian cancer.

BACKGROUND: GP-2250, a novel analog of taurultam (TRLT), has emerged as a potent anti-neoplastic drug; however, the mechanisms underlying its effects are not well understood. Here, we investigated the mechanism of action and the biological effects of GP-2250 using in vitro and in vivo models. METHODS: We carried out a series of in vitro (MTT assay, Annexin V/PI assay, colony formation assay, reverse-phase protein array [RPPA], and HRLC/IC analysis) to determine the biological activity of GP-2250 and investigate the mechanism of action. In vivo experiments were carried out to determine the therapeutic efficacy of GP-2250 alone and in combination with standard-of-care drugs (e.g., paclitaxel, cisplatin, topotecan, and poly ADP-ribose polymerase [PARP] inhibitors). RESULTS: We investigated the cytotoxic effect of GP-2250 in 10 ovarian cancer cell lines and found GP-2250 combined with a PARP inhibitor had the greatest synergy. RPPA revealed that GP-2250 inhibited hypoxia-inducible factor-1α, AKT, and mammalian target of rapamycin (mTOR) activation and expression. High-resolution mass spectrometry revealed that hexokinase2 activity and protein expression were significantly reduced by GP-2250 exposure. Furthermore, GP-2250 reduced glycolysis and ATP synthesis in cancer cells. An in vivo pharmacodynamic experiment using the OVCAR8 mouse model demonstrated that 500 mg/kg GP-2250 was effective in downregulating AKT and mTOR activation and expression. In the in vivo therapy experiment using an orthotopic mouse model, a combination of GP-2250 with either PARP inhibitors or bevacizumab showed a significant reduction of tumor weights and nodules compared to those treated with a vehicle, control IgG groups, or monotherapy groups. CONCLUSIONS: Taken together, our data indicate that GP-2250 exerts profound effects on tumor metabolism and, in combination with PARP inhibitors or bevacizumab, showed promising anti-tumor efficacy. These findings could have implications for the clinical development of GP-2250.

Combined cholecystotomy, retrograde hydropulsion, and choledochal stenting to treat extrahepatic biliary tract obstruction in 3 cats.

Extrahepatic biliary tract obstruction (EHBO) is uncommonly encountered in cats. Surgical treatment aims to decompress the biliary tract and insure bile duct patency. In veterinary medicine, cholecystotomy is not widely used in practice. The objective was to describe the use of cholecystotomy, retrograde hydropulsion of choleliths, and choledochal stenting to remove choleliths from the extrahepatic biliary tract back in the gallbladder. Three adult domestic shorthair cats were presented with anorexia, lethargy, and vomiting. Serum biochemistry revealed hyperbilirubinemia and increased hepatic enzymes. Abdominal ultrasonography showed evidence of EHBO requiring surgical intervention. Choleliths were localized in the proximal and middle portions of the common bile duct (CBD) in the first case, in the distal portion of the CBD and within the major duodenal papilla in the second case, and in the middle and distal portions of the CBD in the third case. Cholecystotomy was followed by retrograde hydropulsion of the choleliths into the gallbladder, after which choledochal stenting was performed. Complications were defined as major when requiring additional medical or surgical treatment, or minor when not. Three major complications were reported. In 2 cases, severe anemia requiring blood transfusion occurred 24 h postoperatively; in 1 case, EHBO recurrence was encountered 41 d postoperatively. All cats were discharged within 4 d following surgery. Two cats were still alive at 12 and 14 mo after surgery, respectively. In the last case, owners refused revision surgery and the cat was euthanized. Key clinical message: Cholecystotomy combined with retrograde hydropulsion of choleliths permitted removal of choleliths and decompression of the biliary tract in 3 cats. Major complications included severe anemia and EHBO recurrence.

Cholécystotomie combinée, hydropulsion rétrograde et pose de stent cholédocien pour traiter l'obstruction des voies biliaires extra-hépatiques chez 3 chats. Les obstructions biliaires extra-hépatiques (OBEH) sont peu fréquentes chez le chat. Le traitement chirurgical vise à lever l'obstruction et s'assurer de la perméabilité des voies biliaires. En médecine vétérinaire, la cholécystotomie est une technique peu pratiquée. L'objectif de ce rapport de cas était de décrire l'utilisation de la cholécystotomie, de l'hydropulsion rétrograde des cholélithes et d'une prothèse endoluminale cholédoquale (PEC) pour repousser les cholélithes présents dans les voies biliaires extrahépatiques dans la vésicule biliaire (VB).Trois chats européens adultes ont été présentés pour anorexie, léthargie et vomissements. La biochimie sérique a révélé une hyperbilirubinémie et une augmentation des enzymes hépatiques. L'échographie abdominale a mis en évidence une OBEH nécessitant une intervention chirurgicale. Les cholélithes étaient situés dans la portion proximale et moyenne du canal cholédoque pour le premier cas; dans la portion distale et la papille duodénale majeure dans le second cas; dans la portion moyenne et distale pour le troisième cas. Une cholécystotomie a été suivie d'une rétro-hydropulsion des cholélithes dans la VB, puis une PEC a été placée. Les complications ont été définies comme majeures lorsqu'elles nécessitaient un traitement médical ou chirurgical supplémentaire, ou mineures lorsqu'elles n'en nécessitaient pas.Trois complications majeures ont été rapportées : chez 2 cas, une anémie sévère a été observée 24 h après l'intervention, nécessitant une transfusion sanguine; chez un cas, une récidive d'obstruction biliaire a eu lieu à 41 jours postopératoire. Tous les patients sont sortis de l'hôpital dans les 4 jours suivant l'opération. Deux cas étaient encore en vie 12 et 14 mois après l'intervention. Pour le dernier cas, la seconde chirurgie a été refusée par les propriétaires et le chat a été euthanasié.Message clinique clé :La cholécystotomie combinée à l'hydropulsion rétrograde des cholélithes a permis le retrait de cholélithes obstructives (dont certaines distales) et la décompression du tractus biliaire chez 3 chats. Les complications majeures incluaient une anémie sévère et une récidive d'obstruction biliaire.(Traduit par les auteurs).

Intratracheal cobinamide (vitamin B12 analog) administration increases survivability in rabbits exposed to a lethal dose of inhaled hydrogen sulfide.

BACKGROUND: Hydrogen sulfide is a highly toxic, flammable, and colorless gas. Hydrogen sulfide has been identified as a potential terrorist chemical threat agent in mass-casualty events. Our previous studies showed that cobinamide, a vitamin B12 analog, effectively reverses the toxicity from hydrogen sulfide poisoning. In this study, we investigate the effectiveness of intratracheally administered cobinamide in treating a lethal dose hydrogen sulfide gas inhalation and compare its performance to saline control administration. METHODS: A total of 53 pathogen-free New Zealand White rabbits were used for this study. Four groups were compared: (i) received no saline solution or drug intratracheally (n = 15), (ii) slow drip saline intratracheally (n = 15), (iii) fast drip saline intratracheally (n = 15), and (iv) slow drip cobinamide intratracheally (n = 8). Blood pressure was continuously monitored, and deoxy- and oxyhemoglobin concentration changes were monitored in real-time in vivo using continuous wave near-infrared spectroscopy. RESULTS: The mean (± standard deviation) weight for all animals (n = 53) was 3.87 ± 0.10 kg. The survival rates of the slow cobinamide and the fast saline groups were 75 percent and 60 percent, respectively, while the survival rates in the slow saline and control groups were 26.7 percent and 20 percent, respectively. A log-rank (Mantel-Cox) test showed that survival in fast saline and slow cobinamide groups were significantly greater than those of no saline control and slow saline groups (P < 0.05). The slow and no saline control groups were not significantly different (P = 0.59). The slow cobinamide group did significantly better than the slow saline group (P = 0.021). DISCUSSION: The ability to use intratracheal cobinamide as an antidote to hydrogen sulfide poisoning is a novel approach to mass-casualty care. The major limitations of this study are that it was conducted in a single species at a single inhaled hydrogen sulfide concentration. Repeated investigations in other species and at varying levels of hydrogen sulfide exposure will be needed before any definitive recommendations can be made. CONCLUSIONS: We demonstrated that intratracheal cobinamide and fast saline drip improved survival for hydrogen sulfide gas inhalation in rabbit models. Although further study is required, our results suggest that intratracheal administration of cobinamide and fast saline may be useful in hydrogen sulfide mass-casualty events.

EphA2- and HDAC-Targeted Combination Therapy in Endometrial Cancer.

Endometrial cancer is the most frequent malignant tumor of the female reproductive tract but lacks effective therapy. EphA2, a receptor tyrosine kinase, is overexpressed by various cancers including endometrial cancer and is associated with poor clinical outcomes. In preclinical models, EphA2-targeted drugs had modest efficacy. To discover potential synergistic partners for EphA2-targeted drugs, we performed a high-throughput drug screen and identified panobinostat, a histone deacetylase inhibitor, as a candidate. We hypothesized that combination therapy with an EphA2 inhibitor and panobinostat leads to synergistic cell death. Indeed, we found that the combination enhanced DNA damage, increased apoptosis, and decreased clonogenic survival in Ishikawa and Hec1A endometrial cancer cells and significantly reduced tumor burden in mouse models of endometrial carcinoma. Upon RNA sequencing, the combination was associated with downregulation of cell survival pathways, including senescence, cyclins, and cell cycle regulators. The Axl-PI3K-Akt-mTOR pathway was also decreased by combination therapy. Together, our results highlight EphA2 and histone deacetylase as promising therapeutic targets for endometrial cancer.

Development and Validation of Three Automated High-Throughput Molecular Tests to Detect Monkeypox Virus Infections.

BACKGROUND: The 2022 outbreak of the clade IIb monkeypox virus and subsequent global spread lead to an urgent need for the development of high-throughput, sensitive, and reproducible diagnostic tests. METHODS: We developed 3 assays to detect monkeypox virus, 2 (MPXV+ and MPXV) for m2000 RealTime and 1 (MPXV) for Alinity m platforms. Dual targets in E9L and B6R (MPXV+) and J2L and B7R (MPXV) increased mutation resistance. In silico prediction indicates MPXV+ cross-reactivity with orthopox viruses and specific monkeypox virus detection with MPXV. RESULTS: m2000 RealTime MPXV+ and MPXV assay sensitivity was determined to be 3.2 plaque-forming units/mL using a reference virus culture diluted into universal transport medium (UTM). Alinity m MPXV lower limit of detection was 200 copies/mL using monkeypox virus plasmids in pooled UTM matrix. m2000 RealTime MPXV+ and MPXV assays were validated with lesion swabs in UTM and 1:1 saliva to UTM mixtures. Commercially available and remnant clinical lesion specimens in UTM were tested with RealTime MPXV+, RealTime MPXV and Alinity m MPXV assays and demonstrated high agreement to known mpox (MPX)-positive specimens. CONCLUSIONS: RealTime MPXV+, RealTime MPXV, and Alinity MPXV are high throughput and sensitive assays used for the detection of monkeypox virus. These assays maybe useful during MPX outbreaks.

Exploiting metabolic vulnerabilities after anti-VEGF antibody therapy in ovarian cancer.

Despite modest clinical improvement with anti-vascular endothelial growth factor antibody (AVA) therapy in ovarian cancer, adaptive resistance is ubiquitous and additional options are limited. A dependence on glutamine metabolism, via the enzyme glutaminase (GLS), is a known mechanism of adaptive resistance and we aimed to investigate the utility of a GLS inhibitor (GLSi). Our in vitro findings demonstrated increased glutamine abundance and a significant cytotoxic effect in AVA-resistant tumors when GLSi was administered in combination with bevacizumab. In vivo, GLSi led to a reduction in tumor growth as monotherapy and when combined with AVA. Furthermore, GLSi initiated after the emergence of resistance to AVA therapy resulted in a decreased metabolic conversion of pyruvate to lactate as assessed by hyperpolarized magnetic resonance spectroscopy and demonstrated robust antitumor effects with a survival advantage. Given the increasing population of patients receiving AVA therapy, these findings justify further development of GLSi in AVA resistance.

Pharmacokinetics, Safety, and Tolerability of Glepaglutide, a Long-Acting GLP-2 Analog, in Subjects with Renal Impairment.

BACKGROUND: Glepaglutide is a novel, ready-to-use, long-acting, glucagon-like peptide-2 (GLP-2) analog intended for the treatment of patients with short bowel syndrome (SBS). This study investigated the impact of renal function on the pharmacokinetics and safety of glepaglutide. METHODS: In this 3-site, non-randomized, open-label study, 16 subjects were enrolled: 4 with severe renal impairment (eGFR 15 to < 30 mL/min/1.73 m2), 4 with end stage renal disease (ESRD) not on dialysis (eGFR < 15 mL/min/1.73 m2), and 8 matching controls with normal renal function (eGFR ≥ 90 mL/min/1.73 m2). Blood samples were collected over a 14-day period following a single subcutaneous (SC) dose of glepaglutide 10 mg. Safety and tolerability were assessed throughout the study. The primary pharmacokinetic parameters were area under the curve between dosing and 168 h (AUC0-168 h) and the maximum plasma concentration (Cmax). RESULTS: There was no clinically relevant difference between subjects with severe renal impairment/ESRD and normal renal function with respect to total exposure (AUC0-168 h) and peak plasma concentrations (Cmax) of glepaglutide following a single SC dose. A single SC dose of glepaglutide 10 mg appeared safe and well tolerated in subjects with normal renal function and subjects with severe renal impairment or ESRD. No serious adverse events were reported, and no safety issues were identified. CONCLUSIONS: No difference in glepaglutide pharmacokinetics was seen between renal impaired and normal subjects. Based on this trial, dose adjustment appears not to be warranted in SBS patients with renal impairment. TRIAL REGISTRATION: The trial is registered at http://www. CLINICALTRIALS: gov (NCT04178447) and has the EudraCT number: 2019-001466-15.

Disseminated T-cell lymphoma with non-epitheliotropic cutaneous involvement in a cat with erythematous patches and regenerative anemia.

A 14-y-old, castrated male, diabetic, domestic longhaired cat was presented for investigation of anemia. General examination revealed widespread cutaneous erythematous macules and patches. Hematology and bone marrow aspiration revealed severe regenerative anemia and marked erythroid hyperplasia, respectively. Low numbers of intermediate-to-large, atypical lymphocytes were observed in the blood smear and bone marrow aspirates. Various imaging modalities demonstrated a diffuse pulmonary bronchial pattern, multifocal mural thickening of the urinary bladder, splenomegaly, and mild tri-cavitary effusion. Skin biopsies and cytologic examination of the pleural effusion demonstrated round-cell neoplasia consistent with lymphoma. Autopsy confirmed disseminated T-cell lymphoma, mostly affecting the urinary bladder, stomach, lymph nodes, and interscapular subcutis and muscles. Angiocentrism and nerve infiltration were present. The cutaneous erythematous patches, characterized by perivascular neoplastic lymphocytic infiltrates and angiodestruction, were a manifestation of the disseminated lymphoma in this cat, similar to the lesions reported in humans affected by angioimmunoblastic T-cell lymphoma.

Pharmacokinetics of Glepaglutide, A Long-Acting Glucagon-Like Peptide-2 Analogue: A Study in Healthy Subjects.

BACKGROUND AND OBJECTIVE: Glepaglutide is a novel, long-acting, glucagon-like peptide-2 analogue in a stable aqueous formulation for subcutaneous dosing to treat patients with short bowel syndrome. This study was conducted primarily to characterise the pharmacokinetics of glepaglutide in healthy subjects. METHODS: In this open-label, partially randomised, parallel-group study, healthy subjects were evenly randomised to glepaglutide 5 or 10 mg dosed subcutaneously once weekly for 6 weeks or to a single intravenous infusion of glepaglutide 1 mg. Each group comprised 15 subjects. Blood samples were drawn to determine plasma concentrations of the parent drug and its two main metabolites. Concentrations of glepaglutide were calculated as the sum of these three analytes. Citrulline was included as a pharmacodynamic biomarker. Safety was assessed throughout the study. RESULTS: From a comparison of pharmacokinetic parameters following subcutaneous versus intravenous dosing, it is concluded that the pharmacokinetics of glepaglutide following subcutaneous dosing are primarily determined by slow release of the two main glepaglutide metabolites from a subcutaneous depot. For subcutaneous dosing once weekly, the two main metabolites accounted for >98% of the overall glepaglutide exposure at steady state, with the parent drug contributing to less than 1% of exposure. The estimated mean (95% confidence interval) effective half-life for glepaglutide 5 and 10 mg was 124 (73-185) h and 88 (31-146) h, respectively. There was an increase in the citrulline concentration for both glepaglutide subcutaneous dose levels. No safety issues were identified. CONCLUSIONS: Slow release of active metabolites following subcutaneous dosing leads to a significantly protracted pharmacokinetic profile for glepaglutide. These results support that once- or twice-weekly subcutaneous dosing of glepaglutide could be an efficacious therapy for intestinal rehabilitation. GOV IDENTIFIER: NCT03279302.

Rational Combination of CRM1 Inhibitor Selinexor and Olaparib Shows Synergy in Ovarian Cancer Cell Lines and Mouse Models.

CRM1 inhibitors have demonstrated antitumor effects in ovarian and other cancers; however, rational combinations are largely unexplored. We performed a high-throughput drug library screen to identify drugs that might combine well with selinexor in ovarian cancer. Next, we tested the combination of selinexor with the top hit from the drug screen in vitro and in vivo Finally, we assessed for mechanisms underlying the identified synergy using reverse phase protein arrays (RPPA). The drug library screen assessing 688 drugs identified olaparib (a PARP inhibitor) as the most synergistic combination with selinexor. Synergy was further demonstrated by MTT assays. In the A2780luc ip1 mouse model, the combination of selinexor and olaparib yielded significantly lower tumor weight and fewer tumor nodules compared with the control group (P < 0.04 and P < 0.03). In the OVCAR5 mouse model, the combination yielded significantly fewer nodules (P = 0.006) and markedly lower tumor weight compared with the control group (P = 0.059). RPPA analysis indicated decreased expression of DNA damage repair proteins and increased expression of tumor suppressor proteins in the combination treatment group. Collectively, our preclinical findings indicate that combination with selinexor to expand the utility and efficacy of PARP inhibitors in ovarian cancer warrants further exploration.

The hidden role of paxillin: localization to nucleus promotes tumor angiogenesis.

Paxillin (PXN), a key component of the focal adhesion complex, has been associated with cancer progression, but the underlying mechanisms are poorly understood. The purpose of this study was to elucidate mechanisms by which PXN affects cancer growth and progression, which we addressed using cancer patient data, cell lines, and orthotopic mouse models. We demonstrated a previously unrecognized mechanism whereby nuclear PXN enhances angiogenesis by transcriptionally regulating SRC expression. SRC, in turn, increases PLAT expression through NF-ĸB activation; PLAT promotes angiogenesis via LRP1 in endothelial cells. PXN silencing in ovarian cancer mouse models reduced angiogenesis, tumor growth, and metastasis. These findings provide a new understanding of the role of PXN in regulating tumor angiogenesis and growth.

Filtering input fluctuations in intensity and in time underlies stochastic transcriptional pulses without feedback.

Stochastic pulsatile dynamics have been observed in an increasing number of biological circuits with known mechanism involving feedback control and bistability. Surprisingly, recent single-cell experiments in Escherichia coli flagellar synthesis showed that flagellar genes are activated in stochastic pulses without the means of feedback. However, the mechanism for pulse generation in these feedbackless circuits has remained unclear. Here, by developing a system-level stochastic model constrained by a large set of single-cell E. coli flagellar synthesis data from different strains and mutants, we identify the general underlying design principles for generating stochastic transcriptional pulses without feedback. Our study shows that an inhibitor (YdiV) of the transcription factor (FlhDC) creates a monotonic ultrasensitive switch that serves as a digital filter to eliminate small-amplitude FlhDC fluctuations. Furthermore, we find that the high-frequency (fast) fluctuations of FlhDC are filtered out by integration over a timescale longer than the timescale of the input fluctuations. Together, our results reveal a filter-and-integrate design for generating stochastic pulses without feedback. This filter-and-integrate mechanism enables a general strategy for cells to avoid premature activation of the expensive downstream gene expression by filtering input fluctuations in both intensity and time so that the system only responds to input signals that are both strong and persistent.

Enhanced Immunotherapy with LHRH-R Targeted Lytic Peptide in Ovarian Cancer.

Here, we examined the role of EP-100 [luteinizing hormone-releasing hormone (LHRH) ligand joined to a lytic peptide], improving the efficacy of immune checkpoint blockade. LHRH-R-positive murine ovarian cancer cells (ID8, IG10, IF5, and 2C12) were sensitive to EP-100 and were specifically killed at low micromolar levels through LHRH-R. EP-100 increased PD-L1 levels on murine ovarian cancer cells. In vivo syngeneic mouse models (ID8 and IG10) demonstrated that single-agent EP-100 reduced tumor volume, tumor weight, and ascites volume. The greatest reductions in tumor and ascites volume were observed with the combination of EP-100 with an anti-PD-L1 antibody. Immune profiling analysis showed that the population of CD8+ T cells, natural killer cells, dendritic cells, and macrophages were significantly increased in tumor and ascitic fluid samples treated with anti-PD-L1, EP-100, and the combination. However, monocytic myeloid suppressor cells, B cells, and regulatory T cells were decreased in tumors treated with anti-PD-L1, EP-100, or the combination. In vitro cytokine arrays revealed that EP-100 induced IL1α, IL33, CCL20, VEGF, and Low-density lipoprotein receptor (LDLR) secretion. Of these, we validated increasing IL33 levels following EP-100 treatment in vitro and in vivo; we determined the specific biological role of CD8+ T-cell activation with IL33 gene silencing using siRNA and Cas9-CRISPR approaches. In addition, we found that CD8+ T cells expressed very low level of LHRH-R and were not affected by EP-100. Taken together, EP-100 treatment had a substantial antitumor efficacy, particularly in combination with an anti-PD-L1 antibody. These results warrant further clinical development of this combination.

GnRH-R-Targeted Lytic Peptide Sensitizes BRCA Wild-type Ovarian Cancer to PARP Inhibition.

EP-100 is a synthetic lytic peptide that specifically targets the gonadotropin-releasing hormone receptor on cancer cells. To extend the utility of EP-100, we aimed to identify effective combination therapies with EP-100 for ovarian cancer and explore potential mechanisms of this combination. A series of in vitro (MTT assay, immunoblot analysis, reverse-phase protein array, comet assay, and immunofluorescence staining) and in vivo experiments were carried out to determine the biological effects of EP-100 alone and in combination with standard-of-care drugs. EP-100 decreased the viability of ovarian cancer cells and reduced tumor growth in orthotopic mouse models. Of five standard drugs tested (cisplatin, paclitaxel, doxorubicin, topotecan, and olaparib), we found that the combination of EP-100 and olaparib was synergistic in ovarian cancer cell lines. Further experiments revealed that combined treatment of EP-100 and olaparib significantly increased the number of nuclear foci of phosphorylated histone H2AX. In addition, the extent of DNA damage was significantly increased after treatment with EP-100 and olaparib in comet assay. We performed reverse-phase protein array analyses and identified that the PI3K/AKT pathway was inhibited by EP-100, which we validated with in vitro experiments. In vivo experiment using the HeyA8 mouse model demonstrated that mice treated with EP-100 and olaparib had lower tumor weights (0.06 ± 0.13 g) than those treated with a vehicle (1.19 ± 1.09 g), EP-100 alone (0.62 ± 0.78 g), or olaparib alone (0.50 ± 0.63 g). Our findings indicate that combining EP-100 with olaparib is a promising therapeutic strategy for ovarian cancer.

Asymmetric molecular modification of viologens for highly stable electrochromic devices.

Viologens are one of the most well-known electrochromic (EC) chromophores. In particular, symmetric dialkyl viologens have been widely used in EC devices (ECDs), but suffer from the formation of viologen radical cation dimers that deteriorate device performance. In this work, we propose an effective route to suppress dimer formation through molecularly altering one of the N-substituents. We prepare 1-benzyl-1'-heptyl viologens and find that such asymmetric molecular structures attribute to the suppression of dimer production when used as EC chromophores. The suppression of dimer formation allows us to drive the device at relatively higher voltages, so that we could achieve viologen-based ECDs showing large transmittance changes between colored and bleached states, efficient and fast coloration, and stable coloration/bleaching cyclic operation. The results indicate that high-performance ECDs can be realized by utilizing viologens containing asymmetric molecular structures.

Regression Analysis of Local Skin Reactions to Predict Clearance of Actinic Keratosis on the Face in Patients Treated With Ingenol Mebutate Gel: Experience from Randomized Controlled Trials.

Ingenol mebutate gel, a topical field treatment for actinic keratosis (AK), elicits inflammatory application-site reactions in most patients. This analysis explored the relationship between the intensity of local skin reactions (LSRs) and AK clearance, measured by the reduction in AK count from baseline in 218 patients who were treated for AK on the face in the pivotal Phase 3 studies. The analysis modeled the AK count at week 8, adjusted for baseline count, with the composite LSR score at 1 day after the last treatment application for each patient as a predictor to estimate the mean and 90% prediction interval for the percent reduction in AK count. The predicted mean percent reduction in AK count was higher in patients with higher composite LSR scores. Lower composite scores demonstrated a variable, less predictive percentage reduction in efficacy. Therefore, a large inflammatory reaction from ingenol mebutate gives a more reliable prognosis for improved AK clearance.

J Drugs Dermatol. 2017;16(2):112-114.

Variables in Cryosurgery Technique Associated With Clearance of Actinic Keratosis.

BACKGROUND: Cryosurgery is the most commonly used method to treat actinic keratosis (AK). Cryosurgical methods are not standardized. OBJECTIVE: To examine differences in the spray techniques used for liquid nitrogen cryosurgery when treating AKs of the head, and the effect of these variations in technique on rates of complete clearance of AKs. MATERIALS AND METHODS: Patients were those from the FIELD-1 study, who received cryosurgery as per the investigators' usual practice to all AKs. This was followed by topical treatment with either vehicle gel or ingenol mebutate gel, 0.015%, after 3 weeks. The investigator recorded the average duration of cryosurgery spray used, the number of freeze-thaw cycles, and the distance from the tip of the spray device to the AK. Clearance rates were determined at Week 11. RESULTS: Less-aggressive freezing techniques were used for AKs on the face than for those on the scalp. However, higher rates of complete clearance on the face and scalp were associated with more-aggressive freezing techniques. CONCLUSION: Patients with AKs on the face receive less-aggressive cryosurgery than do patients with AKs on the scalp.

Relationship between severity of the local skin reactions and the rate of local skin reaction resolution in patients treated with ingenol mebutate gel.

BACKGROUND: Ingenol mebutate gel is a topical field treatment for actinic keratosis (AK). The treatment elicits application-site reactions in most patients. This analysis evaluated the relationship between the severity of reactions and the speed of their resolution. METHODS: Patients in Phase III studies were treated for AKs on the face (n=218), scalp (n=56), and trunk and extremities (n=209). All of the patients were treated with either ingenol mebutate gel 0.015% once daily for three consecutive days (face/scalp) or ingenol mebutate gel 0.05% once daily for two consecutive days (trunk/extremities). Local skin reactions (LSRs) were assessed on a 5-point scale from 0 to 4 in six categories, yielding composite scores in the range of 0 to 24. RESULTS: The composite LSR score on the day after the last application of ingenol mebutate gel was an important predictor of the speed of resolution of LSRs. The rate of resolution was greatest for AKs treated on the face, followed by the scalp, and then the trunk and extremities. All patients were expected to have minimal LSR scores for the face and scalp at 2 weeks, and for the trunk and extremities at 4 weeks. CONCLUSION: The absolute reduction in LSR scores was proportional to the composite LSR score on the day after the last application of ingenol mebutate gel treatment. The rate of resolution for LSRs was dependent on the anatomic site treated as well as the day 4 composite score.