Phase II Trial Assessing the Repeatability and Tumor Uptake of [68Ga]Ga-HER2 Single-Domain Antibody PET/CT in Patients with Breast Carcinoma

Human epidermal growth factor receptor 2 (HER2) status is used for decision-making in breast carcinoma treatment. The status is obtained through immunohistochemistry or in situ hybridization. These two methods have the disadvantage of necessitating tissue sampling, which is prone to error due to tumor heterogeneity or interobserver variability. Whole-body imaging might be a solution to map HER2 expression throughout the body. Methods: Twenty patients with locally advanced or metastatic breast carcinoma (5 HER2-positive and 15 HER2-negative patients) were included in this phase II trial to assess the repeatability of uptake quantification and the extended safety of the [68Ga]Ga-NOTA-anti-HER2 single-domain antibody (sdAb). The tracer was injected, followed by a PET/CT scan at 90 min. Within 8 d, the procedure was repeated. Blood samples were taken for antidrug antibody (ADA) assessment and liquid biopsies. On available tissues, immunohistochemistry, in situ hybridization, and mass spectrometry were performed to determine the correlation of HER2 status with uptake values measured on PET. If relevant preexisting [18F]FDG PET/CT images were available (performed as standard of care), a comparison was made. Results: With a repeatability coefficient of 21.8%, this imaging technique was repeatable. No clear correlation between PET/CT uptake values and pathology could be established, as even patients with low levels of HER2 expression showed moderate to high uptake. Comparison with [18F]FDG PET/CT in 16 patients demonstrated that in 7 patients, [68Ga]Ga-NOTA-anti-HER2 shows interlesional heterogeneity within the same patient, and [18F]FDG uptake did not show the same heterogeneous uptake in all patients. In some patients, the extent of disease was clearer with the [68Ga]Ga-NOTA-anti-HER2-sdAb. Sixteen adverse events were reported but all without a clear relationship to the tracer. Three patients with preexisting ADAs did not show adverse reactions. No new ADAs developed. Conclusion: [68Ga]Ga-NOTA-anti-HER2-sdAb PET/CT imaging shows similar repeatability to [18F]FDG. It is safe for clinical use. There is tracer uptake in cancer lesions, even in patients previously determined to be HER2-low or -negative. The tracer shows potential in the assessment of interlesional heterogeneity of HER2 expression. In a subset of patients, [68Ga]Ga-NOTA-anti-HER2-sdAb uptake was seen in lesions with no or low [18F]FDG uptake. These findings support further clinical development of [68Ga]Ga-NOTA-anti-HER2-sdAb as a PET/CT tracer in breast cancer patients.

Phase I Study of [68Ga]Ga-Anti-CD206-sdAb for PET/CT Assessment of Protumorigenic Macrophage Presence in Solid Tumors (MMR Phase I)

Macrophages play an important role throughout the body. Antiinflammatory macrophages expressing the macrophage mannose receptor (MMR, CD206) are involved in disease development, ranging from oncology to atherosclerosis and rheumatoid arthritis. [68Ga]Ga-NOTA-anti-CD206 single-domain antibody (sdAb) is a PET tracer targeting CD206. This first-in-human study, as its primary objective, evaluated the safety, biodistribution, and dosimetry of this tracer. The secondary objective was to assess its tumor uptake. Methods: Seven patients with a solid tumor of at least 10 mm, an Eastern Cooperative Oncology Group score of 0 or 1, and good renal and hepatic function were included. Safety was evaluated using clinical examination and blood sampling before and after injection. For biodistribution and dosimetry, PET/CT was performed at 11, 90, and 150 min after injection; organs showing tracer uptake were delineated, and dosimetry was evaluated. Blood samples were obtained at selected time points for blood clearance. Metabolites in blood and urine were assessed. Results: Seven patients were injected with, on average, 191 MBq of [68Ga]Ga-NOTA-anti-CD206-sdAb. Only 1 transient adverse event of mild severity was considered to be possibly, although unlikely, related to the study drug (headache, Common Terminology Criteria for Adverse Events grade 1). The blood clearance was fast, with less than 20% of the injected activity remaining after 80 min. There was uptake in the liver, kidneys, spleen, adrenals, and red bone marrow. The average effective dose from the radiopharmaceutical was 4.2 mSv for males and 5.2 mSv for females. No metabolites were detected. Preliminary data of tumor uptake in cancer lesions showed higher uptake in the 3 patients who subsequently progressed than in the 3 patients without progression. One patient could not be evaluated because of technical failure. Conclusion: [68Ga]Ga-NOTA-anti-CD206-sdAb is safe and well tolerated. It shows rapid blood clearance and renal excretion, enabling high contrast-to-noise imaging at 90 min after injection. The radiation dose is comparable to that of routinely used PET tracers. These findings and the preliminary results in cancer patients warrant further investigation of this tracer in phase II clinical trials.

Preoperative Radiotherapy with a Simultaneous Integrated Boost Compared to Chemoradiotherapy for cT3-4 Rectal Cancer: Long-Term Results of a Multicenter Randomized Study

BACKGROUND

Preoperative chemoradiotherapy (CRT) is the standard treatment for T3-4 rectal cancer. Here, we compared image-guided and intensity-modulated RT (IG-IMRT) with a simultaneous integrated boost (SIB) (instead of concomitant chemotherapy) versus CRT in a multi-centric randomized trial.

METHODS

cT3-4 rectal cancer patients were randomly assigned to receive preoperative IG-IMRT 46 Gy/23 fractions plus capecitabine 825 mg/m² twice daily (CRT arm) or IG-IMRT 46 Gy/23 fractions with an SIB to the rectal tumor up to a total dose of 55.2 Gy (RTSIB arm).

RESULTS

A total of 174 patients were randomly assigned between April 2010 and May 2014. Grade 3 acute toxicities were 6% and 4% in the CRT and RTSIB arms, respectively. The mean fractional change in SUVmax at 5 weeks after completion of preoperative RT were -55.8% (±24.0%) and -52.9% (±21.6%) for patients in the CRT arm and RTSIB arm, respectively (p = 0.43). The pathologic complete response rate was 24% with CRT compared to 14% with RTSIB. There were no differences in 5-year overall survival (OS), progression-free survival (PFS) or local control (LC).

CONCLUSIONS

The preoperative RTSIB approach was not inferior to CRT in terms of metabolic response, toxicity, OS, PFS and LC, and could be considered an available option for patients unfit for fluorouracil-based CRT.

Low-Dose Bevacizumab for the Treatment of Focal Radiation Necrosis of the Brain (fRNB): A Single-Center Case Series

Focal radiation necrosis of the brain (fRNB) is a late adverse event that can occur following the treatment of benign or malignant brain lesions with stereotactic radiation therapy (SRT) or stereotactic radiosurgery (SRS). Recent studies have shown that the incidence of fRNB is higher in cancer patients who received immune checkpoint inhibitors. The use of bevacizumab (BEV), a monoclonal antibody that targets the vascular endothelial growth factor (VEGF), is an effective treatment for fRNB when given at a dose of 5-7.5 mg/kg every two weeks. In this single-center retrospective case series, we investigated the effectiveness of a low-dose regimen of BEV (400 mg loading dose followed by 100 mg every 4 weeks) in patients diagnosed with fRNB. A total of 13 patients were included in the study; twelve of them experienced improvement in their existing clinical symptoms, and all patients had a decrease in the volume of edema on MRI scans. No clinically significant treatment-related adverse effects were observed. Our preliminary findings suggest that this fixed low-dose regimen of BEV can be a well-tolerated and cost-effective alternative treatment option for patients diagnosed with fRNB, and it is deserving of further investigation.

CTIM-12. A PHASE I CLINICAL TRIAL ON THE INTRACRANIAL ADMINISTRATION OF INCREASING DOSES OF IPILIMUMAB PLUS FIXED DOSE NIVOLUMAB IN PATIENTS WITH RECURRENT GLIOBLASTOMA (RGB)

BACKGROUND

Intra-operative intracerebral (iCE) administration of ipilimumab (IPI) and nivolumab (NIVO) after resection of rGB is safe and resulted in encouraging survival (NCT03233152J; Duerinck et al. JITC 2021).

METHODS

Eligible patients (pts) underwent a maximal safe resection followed by iCE administration of 5 mg IPI plus 10 mg NIVO and implantation of an Ommaya reservoir through which NIVO (10 mg) and IPI (cohort defined doses of 1-, 5- and 10 mg of IPI) were administered intracavitary (iCA) in combination with NIVO (10 mg) intravenously pre- and postoperatively and Q2w thereafter for up to 24w.

RESULTS

20 pts (13 male; median age 58y) were enrolled. One patient was excluded due to an intra-operatively diagnosed epidural bacterial infection. Respectively 4 pts were treated at the 1-, 4 pts at the 5-, and 11 pts at the 10 mg iCA IPI dose level. Median number and range of postoperative iCA administrations of IPI/NIVO was 2 (0-4) at the 1 mg dose level, 5 (1-10) at the 5 mg dose level, and pending for the 10 mg dose level. Most important treatment related adverse events were symptomatic aseptic neutrophilic pleocytosis (3 pts, all treated at the 10 mg IPI dose level), subacute cerebral edema necessitating corticosteroid treatment (5 pts), and bacterial colonization of the Ommaya reservoir (3 pts). There were no G5 AE. Nine pts have progressed and 4 pts died from progressive disease. Molecular-genetic characterization of rGB tissues, analysis of cellular and cytokine content, and NIVO/IPI concentrations in CSV samples are ongoing.

CONCLUSION

Repeated iCA administration of 10 mg NIVO plus 10 mg IPI resulted in treatment limiting aseptic neutrophilic pleocytosis. Safety of the presumed MTD of repeated 10 mg NIVO plus 5 mg IPI iCA will be further investigated.

P06.05.A Repeated intracranial administration of ipilimumab and nivolumab in patients with recurrent glioblastoma (rGB): A multi-cohort adaptive phase I clinical trial

Background

Perioperative intracerebral (iCE) administration of ipilimumab (IPI) and nivolumab (NIVO) in combination with IV NIVO was shown to be feasible, safe and associated with an encouraging survival benefit (Duerinck et al. JITC 2021). In subsequent cohorts, combination of iCE administration with biweekly intracavitary (iCA, via an Ommaya reservoir) administration of increasing doses of IPI and NIVO was investigated.

Methods

Three cohorts were defined according to resectability and postoperative treatment schedule. Patients (pts) in cohort-A and -C underwent a maximal safe resection, pts in cohort-B stereotactic biopsy only. All pts received iCE administration of 10 mg NIVO and 5 mg IPI at the end of the surgical intervention, after which an OR was implanted and an additional 10mg of NIVO and IPI (1, 5 or 10 mg) was administered iCA in cohort-C. All pts received biweekly postoperative NIVO 10 mg IV and iCA administrations of NIVO (3 dose levels were investigated in cohorts-A and -B: 1, 5, or 10 mg) for up to a maximum of 24w postoperatively. In cohort-C, 10 mg of NIVO was complemented with IPI (1, 5, or 10 mg). NGS and RNA gene expression profiling was performed on all tissue samples.

Results

In total, 44 pts were included (A: n= 16, B: n= 16, C: n= 12 recruitment ongoing). All pts in cohort-A and -B are off study treatment. All pts received the predefined dose of iCE IPI/NIVO and at least one administration of the predefined iCA dose. AE were infrequent and mostly not immune-related. Most common AE were fatigue(n=37), headache(n=25), confusion(n=18) and postoperative fever(n=15). Bacterial colonization of the Ommaya port occurred in 6 pts, subacute neurological deterioration requiring corticosteroids in 8 pts. There were no grade 5 AEs. Median PFS was 13w for cohort-A, 5w in cohort-B and 13w in cohort-C. Median OS is 43weeks in A, 29w in B and is not yet reached in cohort-C after median follow-up of 23w. OS did not differ significantly between study cohorts. OS of pts who underwent surgical resection (cohorts-A and -C) compared favorably to a historical cohort of 469 Belgian patients with rGB (treated in three prospective phase II clinical trials and a large multicenter early acces program for bevacizumab).

Conclusions

iCE followed by repeated iCA administrations of increasing doses of NIVO with/without IPI in rGB is feasible and safe without dose limiting AEs. A potential survival benefit seems restricted to pts amenable to surgical resection.

A phase I clinical trial on intracranial administration of autologous myeloid dendritic cells (myDC) in combination with ipilimumab and nivolumab in patients with recurrent glioblastoma (rGB)

2033

Background: Intracerebral administration of ipilimumab (IPI) and nivolumab (NIVO) following resection of rGB was demonstrated to be safe and resulted in encouraging survival (Duerinck, Schwarze et al. JITC 2021; Neyns et al. ESMO 2021). CD1c(BDCA-1)+ and CD141(BDCA-3)+ myDC play a pivotal role in initiating an adaptive anti-tumor immune response by re-licensing cytotoxic T lymphocytes within the tumor microenvironment. Methods: Eligible patients (pts)(diagnosed with rGB following radiation and temozolomide treatment; not in need of steroids) underwent a leukapheresis followed by immunomagnetic bead isolation and cryopreservation of CD1c (BDCA-1)+ / CD141(BDCA-3)+ myDC. At the time of surgery, an escalating number of myDC (1, 10, and 20x106 myDC) were injected into the brain tissue lining the resection cavity following maximal safe resection of the rGB (ICer) or injected intratumorally (ITum) following stereotactic biopsy (STx). IPI (5 mg) plus NIVO (10 mg) were co-injected with myDC. NIVO was administered intracavitary (ICav, 10mg) using an Ommaya port and intravenously (IV, 10mg) Q2w (max 12x). Results: Fourteen pts (9 male; median 48y [range 20-78]) were recruited (resection n = 11; STx n = 2) and underwent a successful leukapheresis and isolation of myDC; peroperative administration of myDC was preceded by resection in 10 pts (1 pt did not undergo surgery due to clinical deterioration/cerebral edema), and by STx in 2 pts. Respectively 6 (incl both pts who underwent a STx), 3, and 4 pts were treated at the 3 dose levels. All pts received ITum/ICer/IV-administrations of IPI and NIVO as planned. Median number of postoperative ICav/IV NIVO-administrations was 7 (range 2-11). Most frequent adverse events (AE) were headache (n = 11), fatigue (n = 9), transient dysphasia (n = 6), and nausea (n = 5). Bacterial colonization of the Ommaya occurred in 3 pts necessitating removal. Immune-related AE were infrequent and mild. No G5 AE occurred. No dose-limiting toxicities were seen with increasing numbers of myDC. After a median follow-up of 54w, 3 pts remain progression-free (after 42+, 51+, 54+ weeks of FU), 6 (46%) pts have died; median PFS is 13w (95% CI 0-26), median OS has not been reached; 6-months PFS- and OS-rate are respectively 30% and 84%, 12-months PFS- and OS-rate are respectively 23% and 51%. OS compares favorably to an historical cohort of Belgian rGB patients (n = 469; Log-Rank p = 0.018). Gene expression profiling of resected tissue, analysis of cellular counts, cytokines, NIVO/IPI-concentrations in on-treatment cerebrospinal fluid samples is ongoing. Conclusions: Intracranial administration of autologous myDC plus IPI and NIVO in combination with IV NIVO was found to be feasible, sufficiently safe and associated with encouraging survival justifying further investigation in pts with resectable rGB. Clinical trial information: NCT03233152.

Is there utility for fluorine-18-fluorodeoxyglucose positron-emission tomography scan before surgery in breast cancer? A 15-year overall survival analysis

BACKGROUND

The prognostic value of preoperative fluorine-18-fluorodeoxyglucose positron-emission tomography (¹⁸F-FDG PET) scan for determining overall survival (OS) in breast cancer (BC) patients is controversial.

AIM

To evaluate the OS predictive value of preoperative PET positivity after 15 years.

METHODS

We performed a retrospective search of the Universitair Ziekenhuis Brussel patient database for nonmetastatic patients who underwent preoperative PET between 2002-2008. PET positivity was determined by anatomical region of interest (AROI) findings for breast and axillary, sternal, and distant sites. The prognostic role of PET was examined as a qualitative binary factor (positive vs negative status) and as a continuous variable [maximum standard uptake value (SUVmax)] in multivariate survival analyses using Cox proportional hazards models. Among the 104 identified patients who received PET, 36 were further analyzed for the SUVmax in the AROI.

RESULTS

Poor OS within the 15-year study period was predicted by PET-positive status for axillary (P = 0.033), sternal (P = 0.033), and combined PET-axillary/sternal (P = 0.008) nodes. Poor disease-free survival was associated with PET-positive axillary status (P = 0.040) and combined axillary/sternal status (P = 0.023). Cox models confirmed the long-term prognostic value of combined PET-axillary/sternal status [hazard ratio (HR): 3.08, 95% confidence interval: 1.42-6.69]. SUVmax of ipsilateral breast and axilla as continuous covariates were significant predictors of long-term OS with HRs of 1.25 (P = 0.048) and 1.54 (P = 0.029), corresponding to relative increase in the risk of death of 25% and 54% per SUVmax unit, respectively. In addition, the ratio of the ipsilateral axillary SUVmax over the contralateral axillary SUVmax was the most significant OS predictor (P = 0.027), with 1.94 HR, indicating a two-fold relative increase of mortality risk.

CONCLUSION

Preoperative PET is valuable for prediction of long-term survival. Ipsilateral axillary SUVmax ratio over the uninvolved side represents a new prognostic finding that warrants further investigation.

Abstract P3-02-05: Assessment of repeatability and uptake quantification of 68GaNOTA-anti-HER2 sdAb PET/CT in patients with locally advanced or metastatic breast cancer

Background: Human epidermal growth factor receptor 2 (HER2) status is an important predictive biomarker in breast cancer (BC). Tumor heterogeneity has been described, with changes in HER2 expression levels between lesions and over the disease course. HER2 expression is assessed on tissue biopsies, at primary diagnosis and in metastatic lesions. A whole-body imaging technique such as PET/CT could help understand expression levels in different lesions. A 68Ga-labeled single domain antibody (sdAb) targeting the HER2 receptor has been developed and proven safe (Keyaerts et al., 2016). Imaging is performed at 90 min post-injection (pi). We report results of a phase II trial to assess the repeatability of the technique in 20 patients and the correlation of tracer uptake with HER2 tissue expression of the lesions present at the time of imaging. Methods: Twenty patients (pts) with a locally advanced or metastatic BC with at least one lesion of minimum 12 mm were included. Pts were injected intravenously with a typical protein mass of 100 µg and a radioactive dose ranging from 98-168 MBq 68GaNOTA-anti-HER2 sdAb. PET/CT images were obtained at 90 min pi. A second tracer injection followed by PET/CT was done with a maximal interval of 8 days. To assess repeatability, up to 5 lesions per pt were selected, with no more than 2 in a single organ. Peak Standard Uptake Values (SUVpeak) of the lesions were measured on both scans and compared with a t-test and Bland-Altman Plots. Images were compared to other available medical or imaging data and interpreted considering the subject’s disease course. Serum and plasma samples were collected before injection and between 60 and 365 days pi and stored for future detection of anti-drug antibodies (ADA) and liquid biopsies analysis for the presence of HER2 amplification. Tissue samples were assessed by central labs using mass spectrometry, immunohistochemistry and in fluorescence situ hybridization. Results: Twenty women with BC (6 HER2+, 14 HER2-) with a mean age of 58.6 y (37-81) were included. Three pts were scanned only once (2 due to withdrawal of consent, 1 due to covid pandemic). Repeatability of the technique was visually scored as excellent. For quantification, 50 lesions were compared on both scans in 17 pts without significant differences between the two measurements (p=0.40). The repeatability coefficient (RC) was 38.2%. The mean absolute percentage difference (MAPD) was 13.6%, comparable to repeat values reported for 18F-FDG. In 3 out of 6 HER2-positive (HER2+) patients, lesions showed high uptake, even better visible than using 18F-FDG in 2 of them. In 2 HER2+ subjects with a negative scan, lesions were confirmed to be true negatives: one patient did not relapse from BC but had tuberculosis; the other was confirmed to have a radiopneumonitis after radiotherapy and no relapse. In 1 HER2+ patient, the uptake was unexpectedly low. However, the HER2 status was also not reconfirmed in the metastatic setting for this subject. In 1 HER2-negative patient, the tumor HER2 status was changed from negative to positive based on a subsequent image-guided biopsy performed in this study. High tracer uptake was also seen in many of the patients presenting with HER2-low BC (IHC 1+ or 2+), indicating the potential of the tracer to detect low-level HER2 expression. Additional correlation to centrally performed tissue and blood analysis is ongoing. Conclusion: 68GaNOTA-Anti-HER2 PET/CT shows high uptake in HER2-expressing BC lesions but also in HER2-low lesions. The technique shows good repeatability and, in some cases, even better sensitivity than 18F-FDG PET/CT. Specificity was confirmed in relapse-free lesions such as tuberculosis and radiopneumonitis. Its sensitivity makes it a promising technique to assess HER2+ and HER2-low lesions in BC patients.

Citation Format: Odrade Gondry, Catarina Xavier, Wim Waelput, Omar Al Dabssi, Marian Vanhoeij, Sandrine Aspeslagh, Sofie Joris, Christel Fontaine, Guy Verfaillie, Jacques De Grève, Katrien Glorieus, Ine Luyten, Frederik Vandenbroucke, Sophie Bourgeois, Laurens Raes, Sheeno Thyparambil, Nick Devoogdt, Ilse Vaneycken, Julie Cousaert, Vicky Caveliers, Hendrik Everaert, Tony Lahoutte, Marleen Keyaerts. Assessment of repeatability and uptake quantification of 68GaNOTA-anti-HER2 sdAb PET/CT in patients with locally advanced or metastatic breast cancer [abstract]. In: Proceedings of the 2021 San Antonio Breast Cancer Symposium; 2021 Dec 7-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2022;82(4 Suppl):Abstract nr P3-02-05.

CTIM-17. INTRA-CRANIAL ADMINISTRATION OF CTLA-4 AND PD-1 IMMUNE CHECKPOINT-INHIBITING MONOCLONAL ANTIBODIES IN RECURRENT GLIOBLASTOMA PATIENTS: A MULTI-COHORT ADAPTIVE PHASE I CLINICAL TRIAL

BACKGROUND: Intracerebral (iCE) administration of nivolumab (NIVO) and ipilimumab (IPI) after resection of recurrent glioblastoma (rGB), followed by repeated intravenous(IV) NIVO was recently shown to be feasible, safe and associated with encouraging survival. Subsequent cohorts were defined to investigate the addition of biweekly intracavitary (iCA) or intrathecal (iTH) NIVO +/- IPI administrations. METHODS Four groups were defined according to rGB resectability and postoperative treatment schedule. Group A and D underwent biopsy, B and C maximal safe resection. All patients received iCE injections of 10 mg/1ml NIVO + 5 mg/1ml IPI at the end of surgery, after which an Ommaya catheter was implanted iCA (A, B and C) or iTH (D). Following surgery, all patients received biweekly IV low-dose NIVO(10mg) combined with iCA/iTH 10 mg NIVO (A and B) + 1, 5 or 10 mg IPI (C and D) for up to 24 weeks. NIVO/IPI concentrations were dosed in the cerebrospinal fluid (CSF). Gene sequencing and RNA gene expression profiling were performed on all tissue samples RESULTS 39pts(27 male; 16 in A, 16 in B, 4 in C, 3 in D; recruitment ongoing in C+D) were enrolled. All patients received the predefined dose of iCE IPI/NIVO. Most frequent AEs were fatigue (n=30), headache (n=19), confusion (n=14), dysphasia (n=13), and fever (n=10). Ommaya infection occurred in 5patients, subacute neurological deterioration requiring corticosteroids in 6patients. There were no G5 AEs. irAEs were infrequent and mild. Median PFS and OS were 5w(95% CI 1-8) and 23w(95% CI 0-53) in A and 13w(95% CI 7-19) and 42w(95% CI 30-54) in B, respectively. >90% of CSF samples had elevated protein levels and lymphocytic pleocytosis. There was no evidence for accumulation of NIVO/IPI in the CSF. CONCLUSION Repeated intracavitary or intrathecal administration of NIVO +/- IPI in rGB is feasible and safe. Favourable survival outcome is seen in patients amenable to surgical resection.

Intracerebral administration of CTLA-4 and PD-1 immune checkpoint blocking monoclonal antibodies in patients with recurrent glioblastoma: a phase I clinical trial

Background

Patients with recurrent glioblastoma (rGB) have a poor prognosis with a median overall survival (OS) of 30–39 weeks in prospective clinical trials. Intravenous administration of programmed cell death protein 1 and cytotoxic T-lymphocyte-associated antigen 4 inhibitors has low activity in patients with rGB. In this phase I clinical trial, intracerebral (IC) administration of ipilimumab (IPI) and nivolumab (NIVO) in combination with intravenous administration of NIVO was investigated.

Methods

Within 24 hours following the intravenous administration of a fixed dose (10 mg) of NIVO, patients underwent a maximal safe resection, followed by injection of IPI (10 mg; cohort-1), or IPI (5 mg) plus NIVO (10 mg; cohort-2) in the brain tissue lining the resection cavity. Intravenous administration of NIVO (10 mg) was repeated every 2 weeks (max. five administrations). Next generation sequencing and RNA gene expression profiling was performed on resected tumor tissue.

Results

Twenty-seven patients were enrolled (cohort-1: n=3; cohort-2: n=24). All patients underwent maximal safe resection and planned IC administrations and preoperative NIVO. Thirteen patients (cohort-1: n=3; cohort-2: n=10) received all five postoperative intravenous doses of NIVO. In cohort-2, 14 patients received a median of 3 (range 1–4) intravenous doses. Subacute postoperative neurological deterioration (n=2) was reversible on steroid treatment; no other central nervous system toxicity was observed. Immune-related adverse events were infrequent and mild. GB recurrence was diagnosed in 26 patients (median progression-free survival (PFS) is 11.7 weeks (range 2–152)); 21 patients have died due to progression. Median OS is 38 weeks (95% CI: 27 to 49) with a 6-month, 1-year, and 2-year OS-rate of, respectively, 74.1% (95% CI: 57 to 90), 40.7% (95% CI: 22 to 59), and 27% (95% CI: 9 to 44). OS compares favorable against a historical cohort (descriptive Log-Rank p>0.003). No significant difference was found with respect to PFS (descriptive Log-Rank test p>0.05). A higher tumor mRNA expression level of B7-H3 was associated with a significantly worse survival (multivariate Cox logistic regression, p>0.029).

Conclusion

IC administration of NIVO and IPI following maximal safe resection of rGB was feasible, safe, and associated with encouraging OS.

Trial registration

NCT03233152.

A phase 2 clinical trial on trametinib and low-dose dabrafenib in advanced pretreated BRAFV600/NRASQ61R/K/L wild-type melanoma (TraMel-WT): Interim efficacy and safety results

9529

Background: The mitogen-activated protein kinase (MAPK) pathway can be activated by alternative driver mutations in BRAFV600/ NRASQ61R/K/L wild-type (wt) melanoma. MEK-inhibitor monotherapy has activity in BRAFV600/ NRASQ61R/K/L wt melanoma, but is associated with considerate skin toxicity. Skin toxicity associated with the MEK-inhibitor trametinib (T) can be effectively mitigated by adding a low dose (50 mg BID) of the BRAF-inhibitor dabrafenib (LD-D) (Awada et al. Ann Oncol 2020). Methods: This two-stage, single-center phase 2 trial investigated T 2 mg QD in patients (pts) with advanced BRAFV600/ NRASQ61R/K/L wt melanoma who previously progressed on treatment with checkpoint inhibitors. In case of dose-limiting T-related skin toxicity, LD-D (50 mg BID) was added to T (pre-amend). The trial was amended in June 2019 to administer T upfront with LD-D (post-amend). Objective response rate (ORR, by RECIST v1.1) served as the primary endpoint. A Simon’s two-stage optimal design was used (p0 0.10; p1 0.30; alpha 0.05; power 0.80): in case of > 1 OR in the first 10 pts, 19 additional pts would be included in stage 2. The trial is considered positive if > 5 OR are observed. Results: As of February 9, 2021, 16 pts (3 pre-amend; 13 post-amend) were included (median age 56.5; male 56.3%; stage IIIB 6.3%, IV-M1a-c 68.8%, IV-M1d 25.0%; ECOG performance status 0-1 93.8%; normal lactate dehydrogenase 56.3%). Median duration of follow-up is 17.9 weeks (wks; range 1.9-90.1). The ORR in 14 evaluable pts is 42.9% (5 confirmed and 1 unconfirmed partial response), the disease control rate is 71.4%. Four OR are ongoing after a median follow-up of 8.0 wks (range 0.0-77.0), 2 responding pts progressed on therapy after respectively 16.6 and 24.0 wks. Four out of 6 OR are observed in pts with MAPK-pathway activating mutations (3 class II BRAF and 1 GNAQ mutation). Eight pts (50.0%) have progressed (median progression-free survival 16.4 wks [95% confidence interval [CI] 6.9-25.9]); 4 pts (25.0%) have died (median overall survival 54.7 wks [95% CI 37.6-71.8]). Adverse events (AE) are observed in all pts (grade [G] 3-4 9 [56.3%]). Two pre-amend pts added on LD-D due to dose-limiting T-related skin toxicity; no clinically relevant T-related skin toxicity was observed post-amend with the upfront addition of LD-D. The most frequent AE were creatine kinase increase (G1-2 11 [68.8%]; G3-4 1 [6.3%]), and anemia and acneiform rash (both G1-2 7 [43.8%]; G3-4 0). Therapy was temporarily interrupted due to AE in 11 pts (68.8%) and permanently interrupted in 1 pt (6.3%) due to recurrent pneumonitis. Conclusions: In this two-stage phase 2 trial, T plus LD-D was found to have promising antitumor activity and acceptable toxicity in pts with advanced pretreated BRAFV600/ NRASQ61R/K/L wt melanoma, especially in the presence of identifiable somatic MAPK-pathway activating mutations. Clinical trial information: NCT04059224.

A Phase 2 Clinical Trial of Trametinib and Low-Dose Dabrafenib in Patients with Advanced Pretreated NRASQ61R/K/L Mutant Melanoma (TraMel-WT)

BACKGROUND

MEK-inhibitor monotherapy has activity in advanced NRAS^Q61R/K/L mutant melanoma but is associated with dose-limiting cutaneous toxicity. The combination of a BRAF- with a MEK-inhibitor at their full dose (as in BRAF^V600E/K mutant melanoma) has low cutaneous toxicity. It is unknown whether a low dose of BRAF-inhibitor can mitigate the skin toxicity associated with full-dose MEK-inhibitor treatment in patients with advanced NRAS^Q61R/K/L mutant melanoma.

METHODS

This two-stage phase 2 clinical trial investigated trametinib 2 mg once daily in patients with advanced NRAS^Q61R/K/L mutant melanoma who were pretreated with immune checkpoint inhibitors. In case of trametinib-related cutaneous toxicity, low-dose dabrafenib (50 mg twice daily) was added to prevent recurrent cutaneous toxicity (pre-amendment). Following an amendment, trametinib was combined upfront with low-dose dabrafenib (post-amendment). Objective response rate (ORR) served as the primary endpoint.

RESULTS

All 6 patients enrolled pre-amendment developed trametinib-related cutaneous toxicity, necessitating treatment interruption. Combining trametinib with low-dose dabrafenib prevented recurrent skin toxicity thereafter. Trametinib-related skin toxicity was effectively mitigated in all 10 patients post-amendment. In all 16 included patients, the ORR and disease control rate was 6.3% (1 partial response) and 50.0%, respectively. The trial was halted after the first stage.

CONCLUSIONS

Combining full-dose trametinib with low-dose dabrafenib can mitigate MEK-inhibitor-related skin toxicity but was insufficiently active in this patient population. This combination can be of further interest for the treatment of MEK-inhibitor-sensitive tumors.

The Value of 18F-FDG PET/CT in Predicting the Response to PD-1 Blocking Immunotherapy in Advanced NSCLC Patients with High-Level PD-L1 Expression

BACKGROUND

The objective of this study was to evaluate if ¹⁸F-fluorodeoxyglucose positron emission tomography/computed tomography (¹⁸F-FDG PET/CT)-derived parameters are useful in predicting response and survival after programmed cell death protein 1 (PD-1) blocking immunotherapy in patients with advanced NSCLC characterized by a high programmed death-ligand 1 (PD-L1) expression (≥50%) on immunohistochemistry.

PATIENTS AND METHODS

In 30 patients with advanced stage IV non-small-cell lung cancer (NSCLC) and high PD-L1 expression, ¹⁸F-FDG PET/CT parameters before start of treatment with PD-1 blocking immunotherapy were evaluated retrospectively. In 24 out of the 30 patients, ¹⁸F-FDG PET/CT was available 8 to 9 weeks after start of the treatment. Response Evaluation Criteria in Solid Tumors (RECIST 1.1) and metabolic responses assessed on ¹⁸F-FDG PET/CT were compared.

RESULTS

Median follow-up was 20 months (range, 4.2-37.6). Median PD-L1 expression was 80%. The objective response rate with RECIST 1.1 was 53.3%. Median progression-free survival (PFS) was 12.4 months (95% confidence interval [CI], 1.0-37.8), and median overall survival (OS) was 14.9 months (95% CI, 2.4-38.2). Baseline ¹⁸F-FDG PET/CT parameters did not differ between responders and non-responders (all P > .05). The maximum standardized uptake value (SUVmax) was the only ¹⁸F-FDG PET/CT parameter associated with PFS (P = .04), with a trend for OS (P = .06). At first evaluation, response according to total metabolic tumor volume (TMTV) and total lesion glycolysis (TLG) were associated with PFS and OS (both P < .0001). This was not the case for RECIST 1.1 (P = .29 for PFS and P = .38 for OS).

CONCLUSION

Clinical response and survival were independent from metabolic tumor volume at baseline. Reduction of metabolic tumor volume after 8 to 9 weeks of treatment was a better predictor for prolonged survival than RECIST 1.1.

A Comprehensive Analysis of Baseline Clinical Characteristics and Biomarkers Associated with Outcome in Advanced Melanoma Patients Treated with Pembrolizumab

Simple Summary

Pembrolizumab, a monoclonal antibody targeting programmed cell death 1, improves the survival of patients with advanced melanoma. This study aimed to investigate the association of baseline clinical characteristics, laboratory and imaging variables, and gene expression profiling scores on tumor tissue analysis of advanced melanoma patients who were treated with pembrolizumab, with survival using univariate and multivariate analysis. Baseline organ function (reflected by the presence of active brain metastases, number of metastatically affected organs, albumin) and systemic inflammatory/immunologic status (reflected by albumin, C-reactive protein, absolute lymphocyte count, neutrophil-to-lymphocyte ratio) are the most important clinical and/or laboratory parameters predictive of survival. Novel biomarkers include the baseline presence of BRAF^V600 or NRAS^Q61/G12/G13 mutant circulating tumor DNA and baseline total metabolic tumor volume assessed by whole-body ¹⁸F-FDG-PET/CT. Gene expression profiling scores by the NanoString PanCancer IO360 panel were not conclusive in our patient population.

Abstract

Background: Pembrolizumab improves the survival of patients with advanced melanoma. A comprehensive analysis of baseline variables that predict the benefit of pembrolizumab monotherapy has not been conducted. Methods: Survival data of patients with advanced melanoma who were treated with pembrolizumab in a single university hospital were collected. A multivariate Cox regression analysis was performed to correlate baseline clinical, laboratory, and radiologic characteristics and NanoString IO360 gene expression profiling (GEP) with survival. Results: 183 patients were included (stage IV 85.2%, WHO performance status ≥1 31.1%; pembrolizumab first-line 25.7%), of whom 112 underwent baseline ¹⁸F-FDG-PET/CT imaging, 58 had circulating tumor DNA (ctDNA) assessments, and GEP was available in 27 patients. Active brain metastases, a higher number of metastatic sites, lower albumin and absolute lymphocyte count (ALC), higher C-reactive protein (CRP) and neutrophil-to-lymphocyte ratio, higher total metabolic tumor volume (TMTV), and higher ctDNA levels were associated with worse survival. Elevated lactate dehydrogenase (LDH) ≥ 2ULN (upper limit of normal), CRP ≥ 10ULN, or ALC < 750/mm³ delineate a subpopulation where treatment with pembrolizumab is futile. A TMTV ≥ 80 mL encompassed 17/21 patients with LDH ≥ 2ULN, CRP ≥ 10ULN, or ALC < 750/mm³. No significant associations were observed between baseline GEP scores and survival. Conclusion: Multiple baseline variables correlate with survival on pembrolizumab. TMTV is a more comprehensive baseline biomarker than CRP, LDH, or ALC in predicting the futility of pembrolizumab.

Phase I Trial of 131I-GMIB-Anti-HER2-VHH1, a New Promising Candidate for HER2-Targeted Radionuclide Therapy in Breast Cancer Patients

¹³¹I-GMIB-anti-human epidermal growth factor receptor type 2 (HER2)-VHH1 is a targeted radionuclide theranostic agent directed at HER2-expressing cancers. VHH1 is a single-domain antibody covalently linked to therapeutic ¹³¹I via the linker N-succinimidyl 4-guanidino-methyl-3-iodobenzoate (SGMIB). The phase I study was aimed at evaluating the safety, biodistribution, radiation dosimetry, and tumor-imaging potential of ¹³¹I-GMIB-anti-HER2-VHH1 in healthy volunteers and breast cancer patients. Methods: In a first cohort, 6 healthy volunteers were included. The biodistribution of ¹³¹I-GMIB-anti-HER2-VHH1 was assessed using whole-body (anterior and posterior) planar images obtained at 40 min and at 2, 4, 24, and 72 h after intravenously administered (38 ± 9 MBq) ¹³¹I-GMIB-anti-HER2-VHH1. Imaging data were analyzed using OLINDA/EXM software to determine the dosimetry. Blood and urine samples were obtained over 72 h. In the second cohort, 3 patients with metastatic HER2-positive breast cancer were included. Planar whole-body imaging was performed at 2 and 24 h after injection. Additional SPECT/CT images were obtained after the whole-body images at 2 and 24 h if there was relevant uptake in known cancer lesions. Results: No drug-related adverse events were observed throughout the study. The biologic half-life of ¹³¹I-GMIB-anti-HER2-VHH1 in healthy subjects was about 8 h. After intravenous administration, the compound was eliminated from the blood with a 2.5-h half-life. The drug was eliminated primarily via the kidneys. The drug was stable in circulation, and there was no increased accumulation in the thyroid or stomach. The absorbed dose to the kidneys was 1.54 ± 0.25 mGy/MBq, and to bone marrow it was 0.03 ± 0.01 mGy/MBq. SPECT/CT imaging in patients with advanced breast cancer showed focal uptake of ¹³¹I-GMIB-anti-HER2-VHH1 in metastatic lesions. Conclusion : Because of its favorable toxicity profile and its uptake in HER2-positive lesions, this radiopharmaceutical can offer new therapeutic options to patients who have progressed on trastuzumab, pertuzumab, or trastuzmab emtansine, given its difference in mode-of-action. A dose escalation is planned in a subsequent phase I/II study to assess the therapeutic window of this compound (NCT04467515).

Axitinib plus avelumab in the treatment of recurrent glioblastoma: a stratified, open-label, single-center phase 2 clinical trial (GliAvAx)

BACKGROUND

No treatment demonstrated to improve survival in patients with recurrent glioblastoma (rGB) in a randomized trial. Combining axitinib with the programmed cell death ligand 1 blocking monoclonal antibody avelumab may result in synergistic activity against rGB.

METHODS

Adult patients with rGB following prior surgery, radiation therapy and temozolomide chemotherapy were stratified according to their baseline use of corticosteroids. Patients with a daily dose of ≤8 mg of methylprednisolone (or equivalent) initiated treatment with axitinib (5 mg oral two times per day) plus avelumab (10 mg/kg intravenous every 2 weeks) (Cohort-1). Patients with a higher baseline corticosteroid dose initiated axitinib monotherapy; avelumab was added after 6 weeks of therapy if the corticosteroid dose could be tapered to ≤8 mg of methylprednisolone (Cohort-2). Progression-free survival at 6 months (6-m-PFS%), per immunotherapy response assessment for neuro-oncology criteria, served as the primary endpoint.

RESULTS

Between June 2017 and August 2018, 54 patients (27 per cohort) were enrolled and initiated study treatment (median age: 55 years; 63% male; 91% Eastern Cooperative Oncology Group Performance Status 0-1). Seventeen (63%) patients treated in Cohort-2 received at least one dose of avelumab. The 6-m-PFS% was 22.2% (95% CI 6.5% to 37.9%) and 18.5% (95% CI 3.8% to 33.2%) in Cohort-1 and Cohort-2, respectively; median overall survival was 26.6 weeks (95% CI 20.8 to 32.4) in Cohort-1 and 18.0 weeks (95% CI 12.5 to 23.5) in Cohort-2. The best objective response rate was 33.3% and 22.2% in Cohort-1 and Cohort-2, respectively, with a median duration of response of 17.9 and 19.0 weeks. The most frequent treatment-related adverse events were dysphonia (67%), lymphopenia (50%), arterial hypertension and diarrhea (both 48%). There were no grade 5 adverse events.

CONCLUSION

The combination of avelumab plus axitinib has an acceptable toxicity profile but did not meet the prespecified threshold for activity justifying further investigation of this treatment in an unselected population of patients with rGB.

Baseline biomarkers correlated with outcome in advanced melanoma treated with pembrolizumab monotherapy

e22041

Background: Pembrolizumab (PEMBRO) improves survival in advanced melanoma (MEL). This research investigates baseline (BL) biomarkers that predict long-term benefit on PEMBRO monotherapy. Methods: Outcome data on patients (pts) with advanced cutaneous/mucosal MEL treated with PEMBRO in our institution were collected after pt consent. Responses were evaluated using the immune-related response criteria. Total metabolic tumor volume (TMTV), assessed by 18-fluorodeoxyglucose positron emission tomography/computed tomography, was calculated as the sum of all tumor-associated voxels with a standardized uptake value (SUV) above the mean SUV measured in a reference region in normal liver tissue plus 3 standard deviations using Syngo.via software (Siemens Healthcare). The NanoString PanCancer IO360 panel was used for gene expression profiling (GEP). Results: A total of 196 pts was included in this analysis (median age 60; cutaneous 86%, mucosal 3%, unknown primary 12%; stage III 14%, IV-M1a/b/c 60%, IV-M1d 26%; first-line 24%). Median progression-free survival (PFS) in the population was 20.4 w (95% CI 10.2-30.7); median overall survival (OS) was 143.6 w (95% CI NR-NR). BL WHO Performance Status (PS) > 0 (HR 1.63 [95% CI 1.13-2.37]), C-reactive protein (CRP) > ULN (HR 1.92 [95% CI 1.33-2.77]), absolute lymphocyte count (ALC) < 750/mm³ (HR 2.45 [95% CI 1.32-4.55]) and > 1 metastatic site (HR 1.84 [95% CI 1.23-2.77]) were associated (P≤0.01) with worse PFS in multivariate analysis (Cox regression); BL WHO PS > 0 (HR 2.77 [95% CI 1.82-4.24]), lactate dehydrogenase (LDH) > ULN (HR 1.80 [95% CI 1.16-2.79]) and > 1 metastatic site (HR 1.95 [95% CI 1.16-3.25]) were associated with worse OS (P≤0.011). BL TMTV data were available in 118 pts (60%): BL CRP > ULN (HR 1.83 [95% CI 1.13-2.96]), ALC < 750/mm³ (HR 2.49 [95% CI 1.02-6.08]), > 1 metastatic site (HR 1.71 [95% CI 1.04-2.82]) and BL corticosteroid use (HR 4.62 [95% CI 1.38-15.45]) were associated with worse PFS (P < 0.05). BL WHO PS > 0 (HR 2.82 [95% CI 1.57-5.08]), ALC < 750/mm³ (HR 2.62 [95% CI 1.06-6.51]), history of brain metastases (HR 2.59 [95% CI 1.37-4.91]) and TMTV > 80 mL (HR 3.56 [95% CI 1.82-6.95]) were all associated with worse OS (P≤0.038). GEP data on a representative BL tumor sample were available in 27 pts (14%). Higher apoptosis signature scores were associated with increased probability of OS (HR 0.45 [95% CI 0.33-0.73], P < 0.01). Conclusions: BL TMTV > 80 mL identifies a subgroup of advanced MEL pts with worse outcome on PEMBRO. Increased apoptosis gene signature scores in a subset of patients predict increased OS.

A phase I clinical trial on intratumoral and intracavitary administration of ipilimumab and nivolumab in patients with recurrent glioblastoma

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Background: Intravenous (IV) administration of ipilimumab (IPI) and nivolumab (NIVO) has low activity in recurrent glioblastoma (rGB). Intratumoral (IT) and intracavitary (IC) administration of IPI and NIVO is under evaluation in the GlITIpNi phase I clinical trial. Methods: Patients (pts) with resectable rGB were recruited to cohorts C1, C2 and C4; pts with non-resectable rGB were recruited in C3 (biopsy only). IT administration (brain tissue lining the resection cavity during surgery) of IPI (10 mg)(C1), or IPI (5 mg) plus NIVO (10 mg)(C2, C3 and C4), was followed by IC administration of NIVO at escalating doses of 1, 5 or 10 mg Q2w in both C3 and C4 (via an Ommaya reservoir). In all cohorts, pts received 10 mg NIVO IV Q2w (6x in C1/C2, and 12x in C3/C4). Corticosteroids were contraindicated. Results: Forty-six pts (31 male; median age 56y (38-74); IDH1 R132H mutation in 2 pts in C1/C2; NGS somatic mutation analysis for C3/C4 ongoing) with rGB following resection, RT and temozolomide were enrolled (3, 24, 13 and 6 pts in C1, C2, C3 and C4, respectively). All pts received IT administrations. Pts in C1/C2 received a median of 5 IV NIVO administrations. Study treatment has been completed in all pts in C1/C2, in 9 pts in C3, and in 3 pts in C4; pts received a median of 4 (0-10) and 3 (0-7) postoperative IC/IV administrations in C3 and C4, respectively. Two pts in C2 and 1 pt in C3 had an increased perilesional cerebral edema (G3) with neurological deterioration after surgery/IT-injection, that was reversible with steroids. Most frequent AE were fatigue (32 pts, 64%), fever (20 pts, 44%), and headache (25 pts, 50%). In 4 pts from C3, the Ommaya was removed because of bacterial colonization (asymptomatic). There were no G5 AE. There was no dose/AE correlation with increasing IC NIVO doses in C3/C4. Repetitive CSV analysis during therapy (C3/C4) revealed increased lymphocyte counts in 4 pts; scRNA- and TCR-sequencing is ongoing. Gene expression profiling for C1/C2, and pharmacokinetic analysis of NIVO and IPI in CSV for C3/C4 are ongoing. After a median FU of 62w (16-165) for pts in C1/C2, 16 pts have died; median OS is 71w (95% CI 8-134), 1- and 2y-OS% are respectively 51% (95% CI 31-71), and 34% (95% CI 10-59). OS compares favorably to a historical cohort of Belgian rGB pts (n = 469; Log-Rank p .001). After a median FU of 10w (1-37) for pts in C3/C4, 2 pts have died; median OS has not been reached. One pt in C3 achieved a PR that is ongoing at 12m. Conclusions: IT/IC administration of NIVO and IPI is feasible and sufficiently safe to warrant further investigation in pts with rGB. Clinical trial information: NCT03233152 .

Antitumor Activity of Cabozantinib in Metastatic Adult Ewing Sarcoma: A Case Report

A 49-year-old male with Ewing sarcoma and bone, pleural, lung and mediastinal lymph node metastasis was treated with cabozantinib after four lines of previous systemic treatments. He responded objectively and subjectively well for 8 months. In this heavily pretreated patient, the daily starting dose of 60 mg had to be reduced to 30 mg because of adverse events. We conclude that treatment with cabozantinib administered in further-line was active in this particular patient with metastatic Ewing sarcoma. The underlying mechanism of action remains unclear. Because of a stable disease on a long-term treatment with pazopanib targeting an anti-angiogenic pathway common to both drugs previously administered in this patient, it is hypothesized that the action of cabozantinib could be ascribed to its action on the non-common receptors AXL and c-Met. The potential of cabozantinib should be further investigated more upfront in this disease either alone or in combination with other systemic treatments.

SCIDOT-30. GLITIPNI: A PHASE 1B CLINICAL TRIAL COMBINING SURGICAL RESECTION WITH DIRECT INTRACEREBRAL INJECTION OF IMMUNE CHECKPOINT INHIBITORS IN PATIENTS WITH RECURRENT GLIOBLASTOMA

INTRODUCTION

Intravenous (iv) administration of PD-1 blocking mAb is largely ineffective for the treatment of recurrent glioblastoma (rGB). Combination of iv-ipilimumab (IPI) plus nivolumab (NIVO) is associated with a high incidence of irAE. Intracerebral (ic) administration of immune-checkpoint inhibiting mAb following the resection of rGB could be a more effective and safer alternative to iv-dosing.

METHODS

Patients underwent maximal safe resection of their rGB followed by ic-injection of 10mg IPI (cohort-1) or 5mg IPI plus 10mg NIVO (cohort-2) in the wall of the resection cavity. In both cohorts 10mg nivolumab was administered iv for a max of 6 doses, starting 1 day pre-operatively.

RESULTS

21 pts were included (3 in C-1, 18 in C-2; 8F/13M; median age 56y [range 38–72]; 17 de novo GB, 4 secGB). All patients underwent maximal safe surgical resection followed by ic-injection of IPI and NIVO as planned. Median number of iv-administrations of NIVO was 5 (range 1–8). Treatment was generally well tolerated. Postoperatively, 2 patients experienced a G3 symptomatic increase in perilesional cerebral edema with neurological deterioration, reversible upon steroid treatment. One patient had worsening neurological symptoms related to an inflammatory intracerebral cyst at the resection site, requiring surgical decompression 4 months post-study treatment. Most frequent AEs were fatigue (2pts G3, 8pts G2), postoperative fever (11pts G1) and headache (3pts G2); 1pt developed G3 pneumonitis. No other immune-related AEs or treatment-related deaths occurred. After median follow-up of 60 weeks, median PFS is 14.4 weeks (95% CI 11.2–17.6); 11/21 patients are alive, and 1- and 2y-OS% are respectively 46% (95% CI 19- 73%), and15% (95% CI 0–42%).

CONCLUSION

This is the first study demonstrating the safety and activity of combined surgical resection of rGB with local intracerebral administration of immune checkpoint-inhibiting mAb. Survival compares favorably to historical controls justifying further investigation of this experimental therapy.

ATIM-38. GLITIPNI: A PHASE 1B CLINICAL TRIAL COMBINING SURGICAL RESECTION WITH DIRECT INTRACEREBRAL INJECTION OF IMMUNE CHECKPOINT INHIBITORS IN PATIENTS WITH RECURRENT GLIOBLASTOMA

INTRODUCTION

Intravenous (iv) administration of PD-1 blocking mAb is largely ineffective for the treatment of recurrent glioblastoma (rGB). Combination of iv-ipilimumab (IPI) plus nivolumab (NIVO) is associated with a high incidence of irAE. Intracerebral (ic) administration of immune-checkpoint inhibiting mAb following the resection of rGB could be a more effective and safer alternative to iv-dosing.

METHODS

Patients underwent maximal safe resection of their rGB followed by ic-injection of 10mg IPI (cohort-1) or 5mg IPI plus 10mg NIVO (cohort-2) in the wall of the resection cavity. In both cohorts 10mg nivolumab was administered iv for a max of 6 doses, starting 1 day pre-operatively.

RESULTS

21 pts were included (3 in C-1, 18 in C-2; 8F/13M; median age 56y [range 38–72]; 17 de novo GB, 4 secGB). All patients underwent maximal safe surgical resection followed by ic-injection of IPI and NIVO as planned. Median number of iv-administrations of NIVO was 5 (range 1–8). Treatment was generally well tolerated. Postoperatively, 2 patients experienced a G3 symptomatic increase in perilesional cerebral edema with neurological deterioration, reversible upon steroid treatment. One patient had worsening neurological symptoms related to an inflammatory intracerebral cyst at the resection site, requiring surgical decompression 4 months post-study treatment. Most frequent AEs were fatigue (2pts G3, 8pts G2), postoperative fever (11pts G1) and headache (3pts G2); 1pt developed G3 pneumonitis. No other immune-related AEs or treatment-related deaths occurred. After median follow-up of 60 weeks, median PFS is 14.4 weeks (95% CI 11.2–17.6); 11/21 patients are alive, and 1- and 2y-OS% are respectively 46% (95% CI 19- 73%), and15% (95% CI 0–42%).

CONCLUSION

This is the first study demonstrating the safety and activity of combined surgical resection of rGB with local intracerebral administration of immune checkpoint-inhibiting mAb. Survival compares favorably to historical controls justifying further investigation of this experimental therapy.

Undetectable circulating tumor DNA (ctDNA) levels correlate with favorable outcome in metastatic melanoma patients treated with anti-PD1 therapy

BACKGROUND

Treatment with anti-PD1 monoclonal antibodies improves the survival of metastatic melanoma patients but only a subgroup of patients benefits from durable disease control. Predictive biomarkers for durable benefit could improve the clinical management of patients.

METHODS

Plasma samples were collected from patients receiving anti-PD1 therapy for ctDNA quantitative assessment of BRAFV600 and NRASQ61/G12/G13 mutations.

RESULTS

After a median follow-up of 84 weeks 457 samples from 85 patients were analyzed. Patients with undetectable ctDNA at baseline had a better PFS (Hazard ratio (HR) = 0.47, median 26 weeks versus 9 weeks, p = 0.01) and OS (HR = 0.37, median not reached versus 21.3 weeks, p = 0.005) than patients with detectable ctDNA. Additionally, the HR for death was lower after the ctDNA level became undetectable during follow-up (adjusted HR: 0.16 (95% CI 0.07-0.36), p-value < 0.001). ctDNA levels > 500 copies/ml at baseline or week 3 were associated with poor clinical outcome. Patients progressive exclusively in the central nervous system (CNS) had undetectable ctDNA at baseline and at subsequent assessments. In multivariate analysis adjusted for LDH, CRP, ECOG and number of metastatic sites, the ctDNA remained significant for PFS and OS. A positive correlation was observed between ctDNA levels and total metabolic tumor volume (TMTV), number of metastatic sites and total tumor burden.

CONCLUSIONS

Assessment of ctDNA baseline and during therapy was predictive for tumor response and clinical outcome in metastatic melanoma patients and reflected the tumor burden. ctDNA evaluation provided reliable complementary information during anti-PD1 antibody therapy.

GLIAVAX: A stratified phase II clinical trial of avelumab and axitinib in patients with recurrent glioblastoma

2034

Background: Patients (pts) with recurrent glioblastoma (rGB) have a poor prognosis, and no treatment option demonstrated to improve survival in a randomized trial. Axitinib (AXI), an oral VEGFR 1-3 inhibitor has demonstrated single agent activity in rGB and reduces the need for corticosteroids (CS). Avelumab (AVE) is a fully human anti-PD-L1 IgG1 antibody with clinical activity in various tumor types. Combination of AXI and AVE may improve the outcome of pts with rGB. Methods: This open-label, dual-strata, single-center phase 2 clinical trial investigated the activity of AXI plus AVE in adult pts with rGB following prior surgery, RT and temozolomide. Pts were stratified according to their baseline use of CS. Pts without baseline need for CS initiated treatment with AXI (5 mg oral BID) plus AVE (10 mg/kg IV Q2W) (cohort-1). Pts in need of CS initiated AXI as a monotherapy; AVE could be added to AXI after 6 wks if the CS dose could be tapered to a physiologic dose level or less (cohort-2). Six-month-PFS served as the primary endpoint (with a prespecified threshold of ≥ 50% for cohort-1) according to Fleming one-stage design. Results: Between Jun 2017 and Aug 2018, 54 pts (27 per cohort) were enrolled (med age 55 y [range 19-75]; 63% male; 91% WHO PS 0-1). All pts in cohort-1 and 16 pts (59%) in cohort-2 received at least 1 dose of AVE. The 6-month-PFS was 18% (95% CI 4-33) in both cohorts. At the time of analysis, 2 pts were progression-free and continuing study treatment. Median OS in cohort-1 and -2 was respectively 26 wks (95% CI 21-32) and 18 wks (95% CI 14-22). No clear relation was found between baseline cognitive functioning (Cogstate subtests) and PFS/OS. The best overall response rate (iRANO) was 41% and 26% respectively for pts in cohort-1 and -2. The most frequent all-grade treatment-related adverse events (TRAE) were dysphonia (67%), lymphopenia (50%), diarrhea (48%), hypertension (48%), and fatigue (46%). The incidence of grade 3-4 TRAE was 30%; there were no grade 5 AE. Conclusions: The combination of AVE plus AXI is sufficiently well tolerated but did not meet the threshold for activity justifying further investigation in an unselected population of patients with rGB. Clinical trial information: NCT03291314.

Preoperative [18]fluorodeoxyglucose-positron emission tomography/computed tomography in early stage breast cancer: Rates of distant metastases

AIM

To investigate rates of distant metastases (DM) detected with [18]fluorodeoxyglucose-positron emission tomography/computed tomography (18FDG-PET/CT) in early stage invasive breast cancer.

METHODS

We searched the English language literature databases of PubMed, EMBASE, ISI Web of Knowledge, Web of Science and Google Scholar, for publications on DM detected in patients who had 18FDG-PET/CT scans as part of the staging for early stages of breast cancer (stage I and II), prior to or immediately following surgery. Reports published between 2011 and 2017 were considered. The systematic review was conducted according to the PRISMA guidelines.

RESULTS

Among the 18 total studies included in the analysis, the risk of DM ranged from 0% to 8.3% and 0% to 12.9% for stage I and II invasive breast cancer, respectively. Among the patients with clinical stage II, the rate of occult metastases diagnosed by 18FDG-PET/CT was 7.2% (range, 0%-19.6%) for stage IIA and 15.8% (range, 0%-40.8%) for stage IIB. In young patients (< 40-year-old), 18FDG-PET/CT demonstrated a higher prevalence of DM at the time of diagnosis for those with aggressive histology (i.e., triple-negative receptors and poorly differentiated grade).

CONCLUSION

Young patients with poorly differentiated tumors and stage IIB triple-negative breast cancer may benefit from 18FDG-PET/CT at initial staging to detect occult DM prior to surgery.

Factors determining altered perfusion after acute pulmonary embolism assessed by quantified single-photon emission computed tomography-perfusion scan

AIM OF THE STUDY:

The aim of the study was to analyze the evolution of perfusion (Q)-defects in patients treated for acute pulmonary embolism (PE), correlation with baseline parameters and evaluation of recurrence risk.

METHODS:

This is a single-center prospective observational cohort study in symptomatic normotensive PE. Comparison of the ventilation/perfusion single-photon emission computed tomography (V/Q-SPECT) acquired at baseline with a quantified SPECT (Q-SPECT) repeated at 1 week and 6 months. The Q-defect extent (percentage of total lung volume affected) was measured semiquantitatively. Data collected at baseline were age, gender, body mass index (BMI), history of previous venous thromboembolism (HVTE), Charlson's Comorbidity Score (CcS), plasma troponin-T and D-dimer levels, PE Severity Index, and tricuspid regurgitation jet (TRJ) velocity.

RESULTS:

Forty-six patients (22 men/24 women, mean age 61.7 years (± standard deviation 16.3)) completed the study. At 1 week, 13/46 (28.3 %) and at 6 months 22/46 (47.8%) patients had completely normalized Q-SPECT. Persistence of Q-defects was more frequent in female patients in univariate and multivariate analysis. We found no correlation between the persistence of Q-defects on Q-SPECT and HVTE, BMI, plasma troponin-T, and CcS. However, lower TRJ and younger age were statistically significantly linked to normalization of Q-scans after 6 months of treatment only in univariate analysis. There is no difference in the frequency of recurrent PE in relation to the persistence of Q-defects.

CONCLUSION:

Acute PE patients of female, older age, and higher TRJ in univariate analysis and patients of female in multivariate analysis seem to have a higher risk of persistent Q-defects after 6 months treatment. The presence of residual Q-abnormalities at 6 months was not associated with an increased risk for recurrent PE.

Incidence of Thyroid-Related Adverse Events in Melanoma Patients Treated With Pembrolizumab

CONTEXT

Immune checkpoint blockade is associated with endocrine-related adverse events. Thyroid dysfunction during pembrolizumab therapy, an anti-programmed cell death 1 (PD-1) receptor monoclonal antibody, remains to be fully characterized.

OBJECTIVE

To assess the incidence and characteristics of pembrolizumab-associated thyroid dysfunction.

DESIGN AND SETTING

Thyroid function was monitored prospectively in melanoma patients who initiated pembrolizumab within an expanded access program at a referral oncology center. 18Fluorodeoxyglucose uptake on positron emission tomography/computed tomography (18FDG-PET/CT) was reviewed in cases compatible with inflammatory thyroiditis.

PATIENTS

Ninety-nine patients with advanced melanoma (age, 26.3-93.6 years; 63.6% females) who received at least one administration of pembrolizumab.

MAIN OUTCOME MEASURES

Patient characteristics, thyroid function (TSH, free T4), thyroid autoantibodies, and 18FDG-PET/CT.

RESULTS

Eighteen adverse events of thyroid dysfunction were observed in 17 patients. Thyrotoxicosis occurred in 12 patients, of which nine evolved to hypothyroidism. Isolated hypothyroidism was present in six patients. Levothyroxine therapy was required in 10 of 15 hypothyroid patients. Thyroid autoantibodies were elevated during thyroid dysfunction in four of 10 cases. Diffuse increased 18FDG uptake by the thyroid gland was observed in all seven thyrotoxic patients who progressed to hypothyroidism.

CONCLUSIONS

Thyroid dysfunction is common in melanoma patients treated with pembrolizumab. Hypothyroidism and thyrotoxicosis related to inflammatory thyroiditis are the most frequent presentations. Serial measurements of thyroid function tests are indicated during anti-PD-1 monoclonal antibody therapy. Thyrotoxicosis compatible with inflammatory thyroiditis was associated with diffuse increased 18FDG uptake by the thyroid gland. The prospective role of thyroid autoantibodies should be further investigated, together with the histopathological correlates.

Effective Treatment of Pleural Epitheloid Hemangio-endothelioma with Pazopanib: A Case Report

A patient with a pleural epitheloid hemangio-endothelioma (EHE) who failed to respond to six cycles of initial chemotherapy with iphosphamide and epirubicine was treated with pazopanib in second-line. A significant subjective and objective metabolic response on (18)F-fluoro-deoxyglucose positron-emission tomography-computed tomography was noted. Based on this observation, the role of vasculoendothelial growth factor receptor inhibitors such as pazopanib (or other tyrosine kinase inhibitors), in the treatment of pleural EHE should be established through prospective collaborative studies as upfront medication and in combination with chemotherapy.

Sunitinib Malate plus Lomustine for Patients with Temozolomide-refractory Recurrent Anaplastic or Low-grade Glioma

Tyrosine kinase signaling through the vascular endothelial growth factor receptor 2 (VEGFR2), platelet-derived growth factor receptor- α (PDGFR-α) and KIT cell surface receptors mediates neo-angiogenesis and contributes to cancer cell survival in recurrent anaplastic and low-grade glioma. Thirteen patients with temozolomide-refractory recurrent anaplastic or low-grade glioma were treated with sunitinib malate, a small-molecule tyrosine kinase inhibitor of the VEGFR, PDGFR, and KIT receptors, in combination with lomustine. The most frequent grade 3 and 4 adverse events were fatigue, thrombocytopenia, neutropenia and lymphopenia. The best objective tumor response by Response Assessment in Neuro-Oncology (RANO) criteria was one complete response, one unconfirmed partial response and three cases of stable disease. The median progression-free survival was 1.8 months (95% confidence interval=1.0-2.7 months) with 6-month progression-free survival of 15% (95% confidence interval=0-35%). The median overall survival was 6.7 months (95% confidence interval=0.7-12 months). The investigated combination regimen of sunitinib and lomustine is well-tolerated but insufficiently active to warrant further investigation in an unselected population of patients with temozolomide-refractory recurrent anaplastic and low-grade glioma.

Patterns of response in patients with pretreated metastatic melanoma who received ipilimumab 3 mg/kg in a European expanded access program: five illustrative case reports

Ipilimumab 3 mg/kg was the first agent to improve survival of pretreated advanced melanoma patients. Nonconventional response patterns to ipilimumab have been reported widely, but most of these data were from studies with ipilimumab 10 mg/kg. Here, case reports from five patients treated within an expanded access program (EAP) with ipilimumab at its licensed dose of 3 mg/kg illustrate the efficacy of ipilimumab in an expanded access setting and the range of different tumor response patterns encountered. The durable clinical benefit seen in these patients despite the observed atypical response patterns highlights the necessity for comprehensive clinical decision making.

Parotid gland sparing with helical tomotherapy in head-and-neck cancer

PURPOSE

This study evaluated the ability of helical tomotherapy to spare the function of the parotid glands in patients with head-and-neck cancer by analyzing dose-volume histograms, salivary gland scintigraphy, and quality of life assessment.

METHODS AND MATERIALS

Data from 76 consecutive patients treated with helical tomotherapy (Hi-Art Tomotherapy) at the University Hospital Brussel were analyzed. During planning, priority was given to planning target volume (PTV) coverage: ≥ 95% of the dose must be delivered to ≥ 95% of the PTV. Elective nodal regions received 54 Gy (1.8 Gy/fraction). A dose of 70.5 Gy (2.35 Gy/fraction) was prescribed to the primary tumor and pathologic lymph nodes (simultaneous integrated boost scheme). Objective scoring of salivary excretion was performed by salivary gland scintigraphy. Subjective scoring of salivary gland function was evaluated by the European Organization for Research and Treatment of Cancer quality of life questionnaires Quality of Life Questionnaire-C30 (QLQ-C30) and Quality of Life Questionnaire-Head and Neck 35 (H&N35).

RESULTS

Analysis of dose-volume histograms (DVHs) showed excellent coverage of the PTV. The volume of PTV receiving 95% of the prescribed dose (V95%) was 99.4 (range, 96.3-99.9). DVH analysis of parotid gland showed a median value of the mean parotid dose of 32.1 Gy (range, 17.5-70.3 Gy). The median parotid volume receiving a dose <26 Gy was 51.2%. Quality of life evaluation demonstrated an initial deterioration of almost all scales and items in QLQ-C30 and QLQ-H&N35. Most items improved in time, and some reached baseline values 18 months after treatment.

CONCLUSION

DVH analysis, scintigraphic evaluation of parotid function, and quality of life assessment of our patient group showed that helical tomotherapy makes it possible to preserve parotid gland function without compromising disease control. We recommend mean parotid doses of <34 Gy and doses <26 Gy to a maximum 47% of the parotid volume as planning goals. Intensity-modulated radiotherapy should be considered as standard treatment in patients with head-and-neck cancer.

Phase II trial of sunitinib malate and lomustine in patients with temozolomide refractory recurrent low-grade and anaplastic gliomas

2050

Background: Recurrent low-grade and anaplastic gliomas eventually transform to a higher grade that is characterized by neo-angiogenesis. Sunitinib inhibits multiple tyrosine kinase receptors (including VEGFR, PDGFR and c-Kit) but has no meaningful activity as a mono-therapy for recurrent glioblastoma when given at a daily dose of 37,5 mg (Neyns et al. J Neurooncol. 2011). We investigated sunitinib in combination with lomustine (CCNU) for the treatment of patients (pts) with temozolomide (TMZ) refractory recurrent low-grade or anaplastic glioma. Methods: Pts received a daily dose of 25 mg sunitinib for 28 consecutive days followed by a 14 days treatment-free interval. CCNU was administered as a single dose (80 mg/m²) on day 14 of a 6w cycle. T1 ± Gd and T2/FLAIR weighted MRI images were obtained q6 wks. 18FET-PET was performed at baseline and reassessed in responding pts. Results: 13 pts were enrolled (mean age 40 [range 33-49]; M/F 8/5; KPS 80-90/70-60: 8/5 pts). All pts had PD following surgery, RT and TMZ. In 7 pts, treatment was initiated at 2nd recurrence, in 4 pts at 3rd recurrence and in 2 pts at the 4th recurrence. Most frequent AEs where fatigue (gr 2: n= 3; gr 3: n= 1), thrombopenia (gr 2: n= 1 gr 3: n= 3 gr4: n= 1), neutropenia (gr 2: n= 2; gr3: n= 2; gr4: n= 2) and lymphopenia (gr 2: n=1; gr 3: n=2; gr 4: n=1). In 5/13 pts CCNU had to be discontinued because of AEs. Treatment with sunitinib was continued in these cases without reoccurrence of AEs. BOR according to RANO criteria: 1 CR, 1 PR (not-confirmed) and 2 SD (DCR: 4/13= 31%). In the patient with CR, FET-PET indicated a complete metabolic response. After a mean FU of 7 mths (range 2 -19), 5 pts are alive. The 6-month PFS is 23% (3/13 pts); median PFS is 1,8 mths (95%CI 1.0 - 2,7). A durable disease control was obtained in 3 pts (TTP respectively 14.8, 11.8+ and 19.2+ mths). Conclusions: in this heavily pretreated population with recurrent low-grade and anaplastic glioma the combination of sunitinib and CCNU is associated with acceptable toxicity and offers a durable progression-free survival in a subgroup of pts. Molecular predictive factors identifying the sensitive population would be needed to justify further clinical investigation of this combination.