Platform adaptive trial of novel antivirals for early treatment of COVID-19 In the community (PANORAMIC): protocol for a randomised, controlled, open-label, adaptive platform trial of community novel antiviral treatment of COVID-19 in people at increased risk of more severe disease

INTRODUCTION

There is an urgent need to determine the safety, effectiveness and cost-effectiveness of novel antiviral treatments for COVID-19 in vaccinated patients in the community at increased risk of morbidity and mortality from COVID-19.

METHODS AND ANALYSIS

PANORAMIC is a UK-wide, open-label, prospective, adaptive, multiarm platform, randomised clinical trial that evaluates antiviral treatments for COVID-19 in the community. A master protocol governs the addition of new antiviral treatments as they become available, and the introduction and cessation of existing interventions via interim analyses. The first two interventions to be evaluated are molnupiravir (Lagevrio) and nirmatrelvir/ritonavir (Paxlovid).

ELIGIBILITY CRITERIA

community-dwelling within 5 days of onset of symptomatic COVID-19 (confirmed by PCR or lateral flow test), and either (1) aged 50 years and over, or (2) aged 18-49 years with qualifying comorbidities. Registration occurs via the trial website and by telephone. Recruitment occurs remotely through the central trial team, or in person through clinical sites. Participants are randomised to receive either usual care or a trial drug plus usual care. Outcomes are collected via a participant-completed daily electronic symptom diary for 28 days post randomisation. Participants and/or their Trial Partner are contacted by the research team after days 7, 14 and 28 if the diary is not completed, or if the participant is unable to access the diary. The primary efficacy endpoint is all-cause, non-elective hospitalisation and/or death within 28 days of randomisation. Multiple prespecified interim analyses allow interventions to be stopped for futility or superiority based on prespecified decision criteria. A prospective economic evaluation is embedded within the trial.

ETHICS AND DISSEMINATION

Ethical approval granted by South Central-Berkshire REC number: 21/SC/0393; IRAS project ID: 1004274. Results will be presented to policymakers and at conferences, and published in peer-reviewed journals.

TRIAL REGISTRATION NUMBER

ISRCTN30448031; EudraCT number: 2021-005748-31.

Molnupiravir plus usual care versus usual care alone as early treatment for adults with COVID-19 at increased risk of adverse outcomes (PANORAMIC): an open-label, platform-adaptive randomised controlled trial

BACKGROUND

The safety, effectiveness, and cost-effectiveness of molnupiravir, an oral antiviral medication for SARS-CoV-2, has not been established in vaccinated patients in the community at increased risk of morbidity and mortality from COVID-19. We aimed to establish whether the addition of molnupiravir to usual care reduced hospital admissions and deaths associated with COVID-19 in this population.

METHODS

PANORAMIC was a UK-based, national, multicentre, open-label, multigroup, prospective, platform adaptive randomised controlled trial. Eligible participants were aged 50 years or older-or aged 18 years or older with relevant comorbidities-and had been unwell with confirmed COVID-19 for 5 days or fewer in the community. Participants were randomly assigned (1:1) to receive 800 mg molnupiravir twice daily for 5 days plus usual care or usual care only. A secure, web-based system (Spinnaker) was used for randomisation, which was stratified by age (<50 years vs ≥50 years) and vaccination status (yes vs no). COVID-19 outcomes were tracked via a self-completed online daily diary for 28 days after randomisation. The primary outcome was all-cause hospitalisation or death within 28 days of randomisation, which was analysed using Bayesian models in all eligible participants who were randomly assigned. This trial is registered with ISRCTN, number 30448031.

FINDINGS

Between Dec 8, 2021, and April 27, 2022, 26 411 participants were randomly assigned, 12 821 to molnupiravir plus usual care, 12 962 to usual care alone, and 628 to other treatment groups (which will be reported separately). 12 529 participants from the molnupiravir plus usual care group, and 12 525 from the usual care group were included in the primary analysis population. The mean age of the population was 56·6 years (SD 12·6), and 24 290 (94%) of 25 708 participants had had at least three doses of a SARS-CoV-2 vaccine. Hospitalisations or deaths were recorded in 105 (1%) of 12 529 participants in the molnupiravir plus usual care group versus 98 (1%) of 12 525 in the usual care group (adjusted odds ratio 1·06 [95% Bayesian credible interval 0·81-1·41]; probability of superiority 0·33). There was no evidence of treatment interaction between subgroups. Serious adverse events were recorded for 50 (0·4%) of 12 774 participants in the molnupiravir plus usual care group and for 45 (0·3%) of 12 934 in the usual care group. None of these events were judged to be related to molnupiravir.

INTERPRETATION

Molnupiravir did not reduce the frequency of COVID-19-associated hospitalisations or death among high-risk vaccinated adults in the community.

FUNDING

UK National Institute for Health and Care Research.

A randomised Phase II trial of carboplatin and gemcitabine ± vandetanib in first-line treatment of patients with advanced urothelial cell cancer not suitable to receive cisplatin

OBJECTIVES

To assess the efficacy and tolerability of the dual epidermal growth factor receptor/vascular endothelial growth factor receptor inhibitor, vandetanib, in combination with carboplatin and gemcitabine in the first-line treatment of patients with advanced transitional cell carcinoma urothelial cancer (UC) who were unsuitable for cisplatin.

PATIENTS AND METHODS

From 2011 to 2014, 82 patients were randomised from 16 hospitals across the UK into the TOUCAN double-blind, placebo-controlled randomised Phase II trial, receiving six 21-day cycles of intravenous carboplatin (target area under the concentration versus time curve 4.5, day 1) and gemcitabine (1000 mg/m2 days 1 and 8) combined with either oral vandetanib 100 mg or placebo (once daily). Progression-free survival (PFS; primary endpoint), adverse events, tolerability and feasibility of use, objective response rate and overall survival (OS) were evaluated. Intention-to-treat and per-protocol analyses were used to analyse the primary endpoint.

RESULTS

The 82 patients were randomised 1:1 to vandetanib (n = 40) or placebo (n = 42), and 25 patients (30%) completed six cycles of all allocated treatment. Toxicity Grade ≥3 was experienced in 80% (n = 32) and 76% (n = 32) of patients in the vandetanib and placebo arms, respectively. The median PFS was 6.8 and 8.8 months for the vandetanib and placebo arms, respectively (hazard ratio [HR] 1.07, 95% confidence interval [CI] 0.65-1.76; P = 0.71); the median OS was 10.8 vs 13.8 months (HR 1.41, 95% CI 0.79-2.52; P = 0.88); and radiological response rates were 50% and 55%.

CONCLUSION

There is no evidence that vandetanib improves clinical outcome in this setting. Our present data do not support its adoption as the regimen of choice for first-line treatment in patients with UC who were unfit for cisplatin.

Fulvestrant plus capivasertib versus placebo after relapse or progression on an aromatase inhibitor in metastatic, oestrogen receptor-positive breast cancer (FAKTION): a multicentre, randomised, controlled, phase 2 trial

BACKGROUND

Capivasertib (AZD5363) is a potent selective oral inhibitor of all three isoforms of the serine/threonine kinase AKT. The FAKTION trial investigated whether the addition of capivasertib to fulvestrant improved progression-free survival in patients with aromatase inhibitor-resistant advanced breast cancer.

METHODS

In this randomised, double-blind, placebo-controlled, phase 2 trial, postmenopausal women aged at least 18 years with an Eastern Cooperative Oncology Group performance status of 0-2 and oestrogen receptor-positive, HER2-negative, metastatic or locally advanced inoperable breast cancer who had relapsed or progressed on an aromatase inhibitor were recruited from 19 hospitals in the UK. Enrolled participants were randomly assigned (1:1) to receive intramuscular fulvestrant 500 mg (day 1) every 28 days (plus a loading dose on day 15 of cycle 1) with either capivasertib 400 mg or matching placebo, orally twice daily on an intermittent weekly schedule of 4 days on and 3 days off (starting on cycle 1 day 15) until disease progression, unacceptable toxicity, loss to follow-up, or withdrawal of consent. Treatment allocation was done using an interactive web-response system using a minimisation method (with a 20% random element) and the following minimisation factors: measurable or non-measurable disease, primary or secondary aromatase inhibitor resistance, PIK3CA status, and PTEN status. The primary endpoint was progression-free survival with a one-sided alpha of 0·20. Analyses were done by intention to treat. Recruitment is complete, and the trial is in follow-up. This trial is registered with ClinicalTrials.gov, number NCT01992952.

FINDINGS

Between March 16, 2015, and March 6, 2018, 183 patients were screened for eligibility, of whom 140 (76%) were eligible and were randomly assigned to receive fulvestrant plus capivasertib (n=69) or fulvestrant plus placebo (n=71). Median follow-up for progression-free survival was 4·9 months (IQR 1·6-11·6). At the time of primary analysis for progression-free survival (Jan 30, 2019), 112 progression-free survival events had occurred, 49 (71%) in 69 patients in the capivasertib group compared with 63 (89%) of 71 in the placebo group. Median progression-free survival was 10·3 months (95% CI 5·0-13·2) in the capivasertib group versus 4·8 months (3·1-7·7) in the placebo group, giving an unadjusted hazard ratio (HR) of 0·58 (95% CI 0·39-0·84) in favour of the capivasertib group (two-sided p=0·0044; one-sided log rank test p=0·0018). The most common grade 3-4 adverse events were hypertension (22 [32%] of 69 patients in the capivasertib group vs 17 [24%] of 71 in the placebo group), diarrhoea (ten [14%] vs three [4%]), rash (14 [20%] vs 0), infection (four [6%] vs two [3%]), and fatigue (one [1%] vs three [4%]). Serious adverse reactions occurred only in the capivasertib group, and were acute kidney injury (two), diarrhoea (three), rash (two), hyperglycaemia (one), loss of consciousness (one), sepsis (one), and vomiting (one). One death, due to atypical pulmonary infection, was assessed as possibly related to capivasertib treatment. One further death in the capivasertib group had an unknown cause; all remaining deaths in both groups (19 in the capivasertib group and 31 in the placebo group) were disease related.

INTERPRETATION

Progression-free survival was significantly longer in participants who received capivasertib than in those who received placebo. The combination of capivasertib and fulvestrant warrants further investigation in phase 3 trials.

FUNDING

AstraZeneca and Cancer Research UK.

Tracking endocrine resistance in estrogen-receptor positive breast cancer in ctDNA

e14550

Background: Endocrine therapy is the standard of care treatment for patients with estrogen-receptor positive advanced breast cancer, owing to improved tolerability and comparable efficacy to that of cytotoxic chemotherapy. Half of such cancers will progress through first line therapy (primary endocrine resistance) and half will progress after an initial period of disease control (secondary or acquired endocrine resistance). A significant challenge is to test for and identify biomarkers which can guide the likely success of endocrine therapy as a single agent or in combination with small molecule inhibitors.This is particularly challenging where metastatic deposits reside at sites where biopsy is difficult. Potential biomarkers indicative of resistance to endocrine therapy have been identified and can be detected in circulating tumour DNA (ctDNA). CtDNA is shed from tumours and is detectable in a cancer patient’s bloodstream. Information on mutational profiles can guide an oncologist in the selection of targeted therapy in addition to hormonal therapy. Methods: We have analysed formalin-fixed paraffin-embedded(FFPE) tumour samples and longitudinal liquid biopsies from 19 patients who were treated with fulvestrant in combination with a novel inhibitor of the PIK3CA/AKT pathway with next-generation sequencing using a targeted 44-gene panel. Mutations identified using this technique were tracked during the course of treatment using droplet-digital PCR(ddPCR). Results: 57 samples were tested using a 44-gene panel; 19 FFPE tumour samples and matched ctDNA samples were obtained prior therapy and ctDNA samples at disease progression. Mutations detected in PIK3CA, AKT1, ESR1and TP53 genes were trackable in longitudinal ctDNA samples using ddPCR. The association between ctDNA dynamics and outcome will be presented. Conclusions: Multiple mutations that enable the early detection of treatment failure and resistance can be tracked in ctDNA. Investigating the clinical utility of ctDNA is paramount.

TOUCAN: A randomised phase II trial of carboplatin and gemcitabine +/- vandetanib in first line treatment of advanced urothelial cell cancer in patients who are not suitable to receive cisplatin

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Background: Whilst cisplatin combination therapy remains the standard of care for patients with advanced urothelial cancers, many patients are unsuitable for cisplatin and go on to receive carboplatin combination therapy. Although responses are frequent, overall outcomes remain poor, and there is a high unmet need for more effective first line treatment. Vandetanib is a well-tolerated, oral inhibitor of vascular and epidermal growth factor receptor tyrosine kinases, both of which are implicated in the pathogenesis of urothelial cancers. Methods: Patients with metastatic or inoperable urothelial cancer who had no prior chemotherapy and were unsuitable for cisplatin were randomly allocated to receive carboplatin (AUC 4.5, day 1) plus gemcitabine (1000mg/m2, days 1 and 8) plus either vandetanib (100mg od, days 1-21) (GCV) or matching placebo (GCP) in 21-day cycles up to a total of 6 cycles. Treatment allocation was double-blind. There was a planned safety review after the first 40 patients had received at least one cycle. The primary endpoint was progression free survival (PFS). Sample size (n=82) was calculated using a one-sided alpha of 0.2 and power 80% to detect a HR of 0.65 for PFS. We present the final efficacy results. The trial was coordinated by the Wales Cancer Trials Unit at Cardiff University and funded by Cancer Research UK (CRUK/09/024) and AstraZeneca. Results: Of 82 patients, 40 received GCV. 62 (76%) had a bladder primary, and 56 (68%) had poor renal function. The arms were well balanced except for age > 75 (13 (16%) GCV, 23 (28%) GCP). Median PFS was 8.5 months (m) (95% CI 6.0, 9.7) and 8.8 m (5.8, 9.0) for GCV and GCP respectively (adjusted hazard ratio (HR) 0.93 (0.50, 1.71), P=0.89). Overall survival was 10.8 m (8.0, 13.0) and 13.8 m (11.1, 16.6) for GCV and GCP respectively (adjusted HR 1.38 (0.77, 2.46), P=0.24). Response rates were 50% (n=20) and 55% (n=23) for GCV and GCP. All-grade adverse events were similar but there were significantly more grade 3+ events in the GCV arm. Conclusion: Vandetanib did not improve efficacy of chemotherapy but increased toxicity in advanced urothelial cancer not suitable for cisplatin. Clinical trial information: 68146831.

The biology of antihormone failure in breast cancer

Many estrogen receptor-positive breast cancer patients initially respond to treatment with antihormonal agents such as tamoxifen, but remissions are often followed by acquisition of resistance and ultimately disease relapse. The development of a rationale for the effective treatment of tamoxifen-resistant breast cancer requires an understanding of the complex signal transduction mechanisms that contribute towards loss of antiestrogen response. Interactions between estrogen and growth factor signaling pathways have been identified in estrogen-responsive cells that are thought to reinforce their individual cellular effects on growth and gene responses. Increasing evidence indicates that abnormalities occurring in growth factor signaling pathways, notably the epidermal growth factor receptor (EGFR) signaling pathway, could dramatically influence steroid hormone action and may be critical to antihormonal-resistant breast cancer cell growth. Thus, inhibitory agents targeting growth factor receptors, or their intracellular pathway components, may prove clinically beneficial in antihormone refractory disease. One example, gefitinib ('Iressa', ZD1839), an EGFR-tyrosine kinase inhibitor, is an interesting therapeutic option that may provide benefit in the treatment of antihormonal-resistant breast cancer. Rapid progress with pharmacological and molecular therapeutic agents is now being made. Therapies that target growth factor signaling pathways may prevent development of resistance.

The antiepidermal growth factor receptor agent gefitinib (ZD1839/Iressa) improves antihormone response and prevents development of resistance in breast cancer in vitro

Although many estrogen receptor-positive breast cancers initially respond to antihormones, responses are commonly incomplete with resistance ultimately emerging. Delineation of signaling mechanisms underlying these phenomena would allow development of therapies to improve antihormone response and compromise resistance. This in vitro investigation in MCF-7 breast cancer cells examines whether epidermal growth factor receptor (EGFR) signaling limits antiproliferative and proapoptotic activity of antihormones and ultimately supports development of resistance. It addresses whether the anti-EGFR agent gefitinib (ZD1839/Iressa; TKI: 1 mum) combined with the antihormones 4-hydroxytamoxifen (TAM: 0.1 mum) or fulvestrant (Faslodex; 0.1 mum) enhances growth inhibition and prevents resistance. TAM significantly suppressed MCF-7 growth over wk 2-5, reducing proliferation detected by immunocytochemistry and fluorescence-activated cell sorter cell cycle analysis. A modest apoptotic increase was observed by fluorescence-activated cell sorter and fluorescence microscopy, with incomplete bcl-2 suppression. EGFR induction occurred during TAM response, as measured by immunocytochemistry and Western blotting, with EGFR-positive, highly proliferative resistant growth subsequently emerging. Although TKI alone was ineffective on growth, TAM plus TKI cotreatment exhibited superior antigrowth activity vs. TAM, with no viable cells by wk 12. Cotreatment was more effective in inhibiting proliferation, promoting apoptosis, and eliminating bcl-2. Cotreatment blocked EGFR induction, markedly depleted ERK1/2 MAPK and protein kinase B phosphorylation, and prevented emergence of EGFR-positive resistance. Faslodex plus TKI cotreatment was also a superior antitumor strategy. Thus, increased EGFR evolves during treatment with antihormones, limiting their efficacy and promoting resistance. Gefitinib addition to antihormonal therapy could prove more effective in treating estrogen receptor-positive breast cancer and may combat development of resistance.

Oestrogen Receptor-Mediated Modulation of the EGFR/MAPK Pathway in Tamoxifen-Resistant MCF-7 Cells

Oestrogen receptor (ER) levels are usually maintained on acquisition of tamoxifen resistance in the clinic, however, tumour re-growth is associated with increased expression of epidermal growth factor receptor (EGFR) and activation of the mitogen activated protein kinase (MAPK) pathway. In the present study we have used the ER down-regulator fulvestrant ('Faslodex') to investigate the influence of the ER on growth of a tamoxifen-resistant (TAM-R) human breast cancer cell line. Expression levels of ER mRNA and protein were equivalent in parental wild-type MCF-7 (WT) and TAM-R cells. Fulvestrant eliminated ER protein expression and inhibited proliferation in both cell lines. The growth inhibitory effects of fulvestrant were associated with a decrease in basal EGFR, c-erbB2 and ERK1/2 activity in TAM-R but not WT cells. ER functionality as determined by oestrogen response element (ERE)-luciferase reporter activity and expression of PgR, pS2 and transforming growth factor alpha (TGFalpha) was significantly reduced in TAM-R compared to WT cells and was further decreased by fulvestrant treatment in both cell lines. Epidermal growth factor (EGF) and TGFalpha significantly increased EGFR/MAPK pathway activity in both cell lines. Ligand-induced EGFR/MAPK activation promoted TAM-R cell growth in both the absence and presence of fulvestrant, whereas no proliferative activity was observed under the same conditions in WT cells. These results suggest that the ER modulates EGFR/MAPK signalling efficiency in TAM-R cells possibly through the regulation of TGFalpha availability. This effect may be overcome by the action of exogenous EGFR ligands, which strengthen EGFR/MAPK signalling activity to generate endocrine-insensitive cell growth.

Enhanced epidermal growth factor receptor signaling in MCF7 breast cancer cells after long-term culture in the presence of the pure antiestrogen ICI 182,780 (Faslodex)

This paper describes the establishment of an antiestrogen-resistant MCF7 breast cancer cell subline (FASMCF) by continuous culture of the estrogen-responsive parental line in steroid-depleted, ICI 182,780 (Faslodex; 10(-7) M)-supplemented medium. After a 3-month period of growth suppression, cells began to proliferate in ICI 182,780 at rates similar to those of untreated wild-type cells. Immunocytochemistry showed these cells to have reduced estrogen receptor and an absence of progesterone receptor proteins. RT-PCR and transient transfection studies with estrogen response element-reporter constructs confirmed that ICI 182,780-suppressed estrogen response element-mediated signaling. FASMCF cells show increased dependence upon epidermal growth factor receptor (EgfR)/mitogen-activated protein kinase (MAPK)-mediated signaling. Thus, EgfR protein and messenger RNA, growth responses to transforming growth factor-alpha, and extracellular signal-regulated kinase 1/2 MAPK activation levels are all increased. Unlike wild-type cells, FASMCF cells are highly sensitive to growth inhibition by an EgfR-specific tyrosine-kinase inhibitor (TKI), ZD1839 (Iressa), and an inhibitor of the activation of MEK1 (MAPKK), PD098059. Short-term ( approximately 3 weeks) withdrawal of cells from antiestrogen had no effect on growth or phenotype, whereas longer withdrawal (>10 weeks) appeared to partially reverse the cellular phenotype with increasing estrogen receptor and decreasing EgfR levels. In subsequent studies FASMCF cells were maintained in TKI, where their growth was again suppressed and secondary TKI resistance failed to develop within the 3-month period in which initial ICI 182,780 resistance arose. Furthermore, wild-type cells similarly maintained in combination ICI 182,780 and TKI treatment conditions remained growth arrested (>6 months), with notable cell loss through both reduced rates of cellular proliferation and increased cell death.

Modulation of oestrogen action by receptor gene inhibition

Selective oestrogen receptor downregulators (SERDs) are a class of highly effective steroidal antitumour agents that reduce cellular levels of the oestrogen receptor (ER). In this study, we compared the efficacy by which three novel molecular approaches: (1) antisense oligonucleotides; (2) antisense RNA; and (3) dominant negative mutants are able to act as SERDs. Using transient and, where appropriate, stable gene transfection experiments we found that constitutive overexpression of ER antisense RNA and a hormone-binding domain compromised dominant-negative ER mutant (DNER-1), were most effective at downregulating ER expression and/or activity in vitro.