Clinical Characteristics and Responses to Immune Checkpoint Inhibitors in RET-Aberrant Digestive Tract Tumours.

BACKGROUND: RET plays an oncogenic role, and its aberrations are potentially actionable. However, they have seldom been reported in tumours other than lung or thyroid cancers. The correlation of RET aberrations with clinical characteristics, co-occurring aberrations, and responses to immune checkpoint inhibitors (ICPi) have not been explored in digestive tract tumours. OBJECTIVES: The aim of the study was to elucidate the clinical characteristics, frequently co-altered genes, and treatment responses in RET-aberrant digestive tract tumours. PATIENTS AND METHODS: We retrospectively evaluated patients with digestive tract cancers for RET-aberrant tumours via FoundationOne CDx tumour-based selected genome sequencing from Jan 2016 to Jan 2021. RESULTS: In a median follow-up time of 51 months, a total of 453 patients were analysed. RET-aberrant tumours accounted for 4.4% in the studied population (n = 20), and 1.1% had an oncogenic fusion (n = 5). APC, KRAS, TP53, MSH6 and STK11 were the differentially co-altered genes (all false discovery rates <0.05). The presence of RET aberrations alone was not a significant prognostic factor. Eleven patients with RET-aberrant tumours received ICPi-based treatment and none achieved an objective response. In contrast, 47 patients with non-aberrant tumours received ICPi treatment and had an objective response rate of 27.7% and a significantly longer treatment duration (6.2 vs 2.8 months, p = 0.0008). CONCLUSIONS: Albeit rarely, RET aberrations can be found in digestive tract tumours. Patients with RET-aberrant tumours have a blunted response to ICPi and a comparable prognosis as compared with RET-wild type tumours. Together, these results provide insights into this rare but potentially actionable target in digestive tract tumours.

Improved survival with induction chemotherapy and conversion surgery in locally advanced unresectable pancreatic cancer: a single institution experience.

Both efficacy and tolerability are critical issues in choosing neoadjuvant chemotherapy in patients with unresectable locally advanced pancreatic cancer (LAPC). The optimal regimen and the impact of conversion surgery on patient survival remains insufficiently reported in Asain population. Therefore, we conducted a retrospective study aiming to evaluate the resection rate after different induction chemotherapy regimen and its impact toward survival. All patients with pancreatic cancer treated in our institute from 2013 to 2020, a total of 730 patients, were reviewed and 131 patients with LAPC were identified. For cohort homogeneity, 14 patients receiving induction concurrent chemoradiotherapy initially were excluded and 117 patients receiving induction chemotherapy were included in the study. Most patients (90 of 117, 77%) received triplet induction chemotherapy, including the combination of S1, leucovorin, oxaliplatin and gemcitabine (SLOG) in 48, modified FOLFIRINOX in 21 and the combination of gemcitabine, oxaliplatin, fluorouracil and leucovorin (GOFL) in 21. The tumor response rate (19%-33%), the surgical exploration rate (38%-52%) and the mOS (15.4-23.0 months) were not significantly different among the three triplets. Both GOFL and SLOG regimen had comparable efficacy and less neutropenia as compared to mFOLFIRINOX. Conversion surgery was performed in 34 of 117 (29%) patients after induction chemotherapy. The median overall survival (mOS) in patients with and without conversion surgery were 29.1 and 14.1 months, respectively (P<0.0001). Radiological response alone was not a reliable indicator of successful conversion surgery. Patients who underwent conversion surgery had significantly better survival and thus highlighted the importance of surgical exploration in all patients who did not have progressive disease after induction chemotherapy.

Epidemic Surveillance Models for Containing the Spread of SARS-CoV-2 Variants: Taiwan Experience

ObjectivesTwo kinds of epidemic surveillance models are presented for containing the spread of SARS-CoV-2 variants so as to avert and stamp out a community-acquired outbreak (CAO) with non-pharmaceutical interventions (NPIs), tests, and vaccination. DesignThe surveillance of domestic cluster infections transmitted from imported cases with one-week time lag assessed by the Poisson model and the surveillance of whether, how and when NPIs and test contained the CAO with the SEIR model. SettingsBorder and Community of Taiwan. Main Outcome MeasurementsThe expected number and the upper bound of the 95% credible interval (CrI) of weekly covid-19 cases compared with the observed number for assessing the threshold of a CAO; effective reproductive number (Rt) and the effectiveness of NPIs for containing a CAO. ResultsFor the period of January-September 2020 when the wild type and the D614G period were prevailing, an increase in one imported case prior to one week would lead to 9.54% (95% CrI 6.44% to 12.59%) higher risk of domestic cluster infection that provides a one-week prior alert signal for more stringent NPIs and active testing locally. Accordingly, there was an absence of CAO until the Alpha VOC period of February 2021. However, given level one of NPI alert the risk of domestic cluster infections was gradually elevated to 14.14% (95% CrI 5.41% to 25.10%), leading to the Alpha VOC CAOs of six hotspots around mid-May 2021. It took two-and-half months for containing this CAO mainly with level three of NPI alert and rapid test and partially by the rolling out of vaccination. By applying the SEIR model, the Rt decreased from 4.0 at beginning to 0.7 on 31 July 2021 in parallel with the escalating NPIs from 30% to 90%. Containing a small outbreak of Delta VOC during this CAO period was also evaluated and demonstrated. After controlling the CAO, it again returned to imported-domestic transmission for Delta VOC from July until September 2021, giving an estimate of 10.16% (95% CrI: 7.01% to 13.59%) for the risk of several small cluster infections. However, there was an absence of CAO that resulted from the effectiveness of NPIs and tests, and the rapid expansion of vaccination. ConclusionsAverting and containing CAOs of SARS-CoV-2 variants are demonstrated by two kinds of epidemic surveillance models that have been applied to Taiwan scenario. These two models can be accommodated to monitor the epidemic of forthcoming emerging SARS-CoV-2 VOCs with various circumstances of vaccine coverage, NPIs, and tests in countries worldwide.

SRSF protein kinases 1 and 2 are essential host factors for human coronaviruses including SARS-CoV-2

While vaccines are vital for preventing COVID-19 infections, it is critical to develop new therapies to treat patients who become infected. Pharmacological targeting of a host factor required for viral replication can suppress viral spread with a low probability of viral mutation leading to resistance. In particular, host kinases are highly druggable targets and a number of conserved coronavirus proteins, notably the nucleoprotein (N), require phosphorylation for full functionality. In order to understand how targeting kinases could be used to compromise viral replication, we used a combination of phosphoproteomics and bioinformatics as well as genetic and pharmacological kinase inhibition to define the enzymes important for SARS-CoV-2 N protein phosphorylation and viral replication. From these data, we propose a model whereby SRPK1/2 initiates phosphorylation of the N protein, which primes for further phosphorylation by GSK-3/{beta} and CK1 to achieve extensive phosphorylation of the N protein SR-rich domain. Importantly, we were able to leverage our data to identify an FDA-approved kinase inhibitor, Alectinib, that suppresses N phosphorylation by SRPK1/2 and limits SARS-CoV-2 replication. Together, these data suggest that repurposing or developing novel host-kinase directed therapies may be an efficacious strategy to prevent or treat COVID-19 and other coronavirus-mediated diseases.

Impacts of remdesivir on dynamics and efficacy stratified by the severity of COVID-19: a simulated two-arm controlled study

BackgroundThe impact of remdesivir on length of stay of hospitalization, high-risk state, and death stratified by the severity of COVID-19 at enrollment is controversial. MethodsWe applied a simulated two-arm controlled study design to the data on compassionate use of remdesivir as a secondary analysis. Dynamics of risk states and death from COVID-19 patients defined by the six-point disease severity recommended by the WHO R&D and the time to discharge from hospital were used to evaluate the efficacy of remdesivir treatment compared with standard care. ResultsStratified by the risk state at enrollment, low-risk patients exhibited the highest efficacy of remdesivir in reducing subsequent progression to high-risk state by 67% (relative risk (RR)=0.33,95% CI: 0.30-0.35) and further to death by 55% (RR=0.45, 95%CI: 0.39-0.50). For the medium-risk patients, less but still statistically significant efficacy results were noted in reducing progression to high-risk state by 52% (RR=0.48, 95% CI: 0.45-0.51) and further to death by 40% (RR=0.60, 95% CI:0.54-0.66). High-risk state patients treated with remdesivir led to a 25% statistically significant reduction in death (RR=0.75, 95% CI: 0.69-0.82). Regarding the outcome of discharge, remdesivir treatment was most effective for medium-risk patients at enrollment (RR: 1.41, 95% CI: 1.35-1.47) followed by high-(RR=1.34, 95% CI: 1.27-1.42) and low-risk patients (RR=1.28, 95% CI: 1.25-1.31). ConclusionOur results with a simulated two-arm controlled study have provided a new insight into the precision treatment of remdesivir for COVID-19 patients based on risk-stratified efficacy.