Tumor characteristics of dissociated response to immune checkpoint inhibition in advanced melanoma

INTRODUCTION

Immune checkpoint inhibition (ICI) has improved patients' outcomes in advanced melanoma, often resulting in durable response. However, not all patients have durable responses and the patients with dissociated response are a valuable subgroup to identify mechanisms of ICI resistance.

METHODS

Stage IV melanoma patients treated with ICI and dissociated response were retrospectively screened for available samples containing sufficient tumor at least at two time-points. Included were one patient with metachronous regressive and progressive lesions at the same site, two patients with regressive and novel lesion at different sites, and three patients with regressive and progressive lesions at different sites. In addition, four patients with acquired resistant tumor samples without a matched second sample were included.

RESULTS

In the majority of patients, the progressive tumor lesion contained higher CD8+ T cell counts/mm2 and interferon-gamma (IFNγ) signature level, but similar tumor PD-L1 expression. The tumor mutational burden levels were in 2 out 3 lesions higher compared to the corresponding regressive tumors lesion. In the acquired tumor lesions, high CD8+/mm2 and relatively high IFNγ signature levels were observed. In one patient in both the B2M and PTEN gene a stop gaining mutation and in another patient a pathogenic POLE mutation were found.

CONCLUSION

Intrapatient comparison of progressive versus regressive lesions indicates no defect in tumor T cell infiltration, and in general no tumor immune exclusion were observed.

Immune checkpoint inhibitor-induced neurotoxicity is not associated with seroprevalence of neurotropic infections

BACKGROUND

Immune checkpoint inhibitors (ICI) substantially improve outcome for patients with cancer. However, the majority of patients develops immune-related adverse events (irAEs), which can be persistent and significantly reduce quality of life. Neurological irAEs occur in 1-5% of patients and can induce severe, permanent sequelae or even be fatal. In order to improve the diagnosis and treatment of neurological irAEs and to better understand their pathogenesis, we assessed whether previous neurotropic infections are associated with neurological irAEs.

METHODS

Neurotropic infections that might predispose to ICI-induced neurological irAEs were analyzed in 61 melanoma patients from 3 countries, the Netherlands, Australia and Germany, including 24 patients with neurotoxicity and 37 control patients. In total, 14 viral, 6 bacterial, and 1 protozoal infections previously reported to trigger neurological pathologies were assessed using routine serology testing. The Dutch and Australian cohorts (NL) included pre-treatment plasma samples of patients treated with neoadjuvant ICI therapy (OpACIN-neo and PRADO trials; NCT02977052). In the Dutch/Australian cohort a total of 11 patients with neurological irAEs were compared to 27 control patients (patients without neurological irAEs). The German cohort (LMU) consisted of serum samples of 13 patients with neurological irAE and 10 control patients without any documented irAE under ICI therapy.

RESULTS

The association of neurological irAEs with 21 possible preceding infections was assessed by measuring specific antibodies against investigated agents. The seroprevalence of all the tested viral (cytomegalovirus, Epstein-Barr-Virus, varicella-zoster virus, measles, rubella, influenza A and B, human herpes virus 6 and 7, herpes simplex virus 1 and 2, parvovirus B19, hepatitis A and E and human T-lymphotropic virus type 1 and 2), bacterial (Borrelia burgdorferi sensu lato, Campylobacter jejuni, Mycoplasma pneumoniae, Coxiella burnetti, Helicobacter pylori, Yersinia enterocolitica and Y. pseudotuberculosis) and protozoal (Toxoplasma gondii) infections was similar for patients who developed neurological irAEs as compared to control patients. Thus, the analysis provided no evidence for an association of described agents tested for seroprevalence with ICI induced neurotoxicity.

CONCLUSION

Previous viral, bacterial and protozoal neurotropic infections appear not to be associated with the development of neurological irAEs in melanoma patients who underwent therapy with ICI across 3 countries. Further efforts are needed to unravel the factors underlying neurological irAEs in order to identify risk factors for these toxicities, especially with the increasing use of ICI in earlier stage disease.

L3 Update of the OpACIN and OpACIN-neo trials: 36-months and 24-months relapse-free survival after (neo)adjuvant ipilimumab plus nivolumab in macroscopic stage III melanoma patients

Background

Before adjuvant checkpoint inhibition the 5-year overall survival (OS) rate was poor (<50%) in high-risk stage III melanoma patients. Adjuvant CTLA-4 (ipilimumab, IPI) and PD-1 (nivolumab, NIVO, or pembrolizumab) blockade have been shown to improve relapse-free survival (RFS) and OS (latter only for IPI so far). Due to a broader immune activation neoadjuvant therapy with checkpoint inhibitors might be more effective than adjuvant, as suggested in preclinical experiments. The OpACIN trial compared neoadjuvant versus adjuvant IPI plus NIVO, while the subsequent OpACIN-neo trial tested three different dosing schedules of neoadjuvant IPI plus NIVO without adjuvant therapy. High pathologic response rates of 74–78% were induced by neoadjuvant IPI plus NIVO. Here, we present the 36- and 24-months RFS of the OpACIN and OpACIN-neo trial, respectively.

Materials and Methods

The phase 1b OpACIN trial included 20 stage IIIB/IIIC melanoma patients, which were randomized to receive IPI 3 mg/kg plus NIVO 1 mg/kg either adjuvant 4 cycles or split 2 cycles neoadjuvant and 2 adjuvant. In the phase 2 OpACIN-neo trial, 86 patients were randomized to 2 cycles neoadjuvant treatment, either in arm A: 2x IPI 3 mg/kg plus NIVO 1 mg/kg q3w (n=30), arm B: 2x IPI 1 mg/kg plus NIVO 3 mg/kg q3w (n=30), or arm C: 2x IPI 3 mg/kg q3w followed immediately by 2x NIVO 3 mg/kg q3w (n=26). Pathologic response was defined as <50% viable tumor cells and in both trials centrally reviewed by a blinded pathologist. RFS rates were estimated using the Kaplan-Meier method.

Results

Only 1 of 71 (1.4%) patients with a pathologic response on neoadjuvant therapy had relapsed, versus 16 of 23 patients (69.6%) without a pathologic response, after a median follow-up of 36 months for the OpACIN and 24 months for the OpACIN-neo trial. In the OpACIN trial, the estimated 3-year RFS rate for the neoadjuvant arm was 80% (95% CI: 59%-100%) versus 60% (95% CI: 36%-100%) for the adjuvant arm. Median RFS was not reached for any of the arms within the OpACIN-neo trial. Estimated 24-months RFS rate was 84% for all patients (95% CI: 76%-92%); 90% for arm A (95% CI: 80%-100%), 78% for arm B (95% CI: 63%-96%) and 83% for arm C (95% CI: 70%-100%). Baseline interferon-γ gene expression score and tumor mutational burden predict response.

Conclusions

OpACIN for the first time showed a potential benefit of neoadjuvant IPI plus NIVO versus adjuvant immunotherapy, whereas the OpACIN-neo trial confirmed the high pathologic response rates that can be achieved by neoadjuvant IPI plus NIVO. Both trials show that pathologic response can function as a surrogate markers for RFS.

Clinical trial information

NCT02437279, NCT02977052

Disclosure Information

J.M. Versluis: None. E.A. Rozeman: None. A.M. Menzies: F. Consultant/Advisory Board; Modest; BMS, MSD, Novartis, Roche, Pierre-Fabre. I.L.M. Reijers: None. O. Krijgsman: B. Research Grant (principal investigator, collaborator or consultant and pending grants as well as grants already received); Modest; BMS. E.P. Hoefsmit: None. B.A. van de Wiel: None. K. Sikorska: None. C. Bierman: None. P. Dimitriadis: None. M. Gonzalez: None. A. Broeks: None. R.M. Kerkhoven: None. A.J. Spillane: None. J.B.A.G. Haanen: B. Research Grant (principal investigator, collaborator or consultant and pending grants as well as grants already received); Modest; BMS, MSD, Neon Therapeutics, Novartis. F. Consultant/Advisory Board; Modest; BMS, MSD, Novartis, Pfizer, AZ/MedImmune, Rocher/Genentech, Ipsen, Bayer, Immunocore, SeattleGenetics, Neon Therapeutics, Celsius Therapeutics, Gadet, GSK. W.J. van Houdt: None. R.P.M. Saw: None. H. Eriksson: None. A.C.J. van Akkooi: B. Research Grant (principal investigator, collaborator or consultant and pending grants as well as grants already received); Modest; Amgen, BMS, Novartis. F. Consultant/Advisory Board; Modest; Amgen, BMS, Novartis, MSD Merck, Merck-Pfizer, 4SC. R.A. Scolyer: F. Consultant/Advisory Board; Modest; MSD, Neracare, Myriad, Novartis. T.N. Schumacher: B. Research Grant (principal investigator, collaborator or consultant and pending grants as well as grants already received); Modest; MSD, BMS, Merck. E. Ownership Interest (stock, stock options, patent or other intellectual property); Modest; AIMM Therapeutics, Allogene Therapeutics, Amgen, Merus, Neogene Therapeutics, Neon Therapeutics. F. Consultant/Advisory Board; Modest; Adaptive Biotechnologies, AIMM Therapeutics, Allogene Therapeutics, Amgen, Merus, Neon Therapeutics, Scenic Biotech. Other; Modest; Third Rock Ventures. G.V. Long: F. Consultant/Advisory Board; Modest; Aduro, Amgen, BMS, Mass-Array, Pierre-Fabre, Novartis, Merck MSD, Roche. C.U. Blank: B. Research Grant (principal investigator, collaborator or consultant and pending grants as well as grants already received); Modest; BMS, Novartis, NanoString. E. Ownership Interest (stock, stock options, patent or other intellectual property); Modest; Uniti Cars, Neon Therapeutics, Forty Seven. F. Consultant/Advisory Board; Modest; BMS, MSD, Roche, Novartis, GSK, AZ, Pfizer, Lilly, GenMab, Pierre-Fabre.