A Phase 2 interventional study of Nivolumab in Urachal Cancer, Parathyroid Carcinoma and Fibrolamellar Carcinoma, sponsored by Instituto do Cancer do Estado de São Paulo. Active, not recruiting at 5 sites in Brazil. Open to participants aged 18 Years and older. Per ClinicalTrials.gov, last updated 2026-10-13.
Sponsored by Instituto do Cancer do Estado de São Paulo · Phase 2, Interventional, and Treatment
The ANTARES study is a phase II basket trial designed to evaluate the tissue-agnostic efficacy of the monoclonal anti-PD1 antibody, nivolumab, in patients with advanced or metastatic rare tumors.
The study aims to treat rare malignancies with PD-L1 expression (CPS ≥ 10), regardless of the tumor's tissue type or location. Patients who have not responded to standard treatments will be included, and treatment will last for up to 12 months. The study will assess objective response, progression-free survival, and biomarkers such as PD-L1, ctDNA, and microvesicles, in a multicenter collaborative effort to provide innovative therapeutic options for this underrepresented population
The ANTARES study is a phase II "basket" trial designed to evaluate the tissue-agnostic efficacy of the monoclonal anti-PD1 antibody, nivolumab, in patients with advanced or metastatic rare tumors. A "basket" trial is an innovative type of clinical trial where patients with different types of cancers, but sharing a common molecular feature (in this case, PD-L1 expression), are treated with the same therapy, regardless of the tumor's site of origin. This approach allows for the evaluation of treatments targeting specific molecular characteristics, independent of the primary cancer type.
Rare tumors, as defined by the World Health Organization (WHO), have an incidence of fewer than six cases per 100,000 people per year. Although each rare cancer type is individually uncommon, collectively they account for 25-30% of all malignancies and are often underrepresented in clinical trials due to recruitment challenges and limited funding. As a result, patients with rare cancers generally have a poorer prognosis compared to those with more common tumors.
In this study, patients with advanced or refractory rare malignancies expressing PD-L1, with a combined positive score (CPS) of ≥10, will be treated with nivolumab. Treatment will be administered until disease progression or for a maximum duration of 12 months, aiming to assess the efficacy and safety of this tissue-agnostic immunotherapy approach. Efficacy will be measured according to RECIST v1.1 criteria, with objective response as the primary endpoint. Additionally, the study will assess response biomarkers, including PD-L1, circulating tumor DNA (ctDNA), and microvesicles, to better understand the correlation between biomarker expression and clinical outcomes.
This multicenter trial, with an estimated duration of four years, will be conducted at Institute of Cancer of the State of São Paulo (ICESP) and other partner institutions. The study aims to overcome existing barriers in rare cancer treatment by offering an innovative approach that explores the potential of personalized therapies based on molecular characteristics, rather than the tumor's primary site
63 studies on the registry are indexed under Parathyroid Neoplasms; 19 are open to participants now.
This study's planned enrollment of 28 is below the median of 60 across 38 interventional studies indexed under Parathyroid Neoplasms.
Browse Parathyroid Neoplasms studies →Instituto do Cancer do Estado de São Paulo is the lead sponsor of 91 studies on the registry; 22 are open to participants now.
Counted across the registry records on this site, refreshed daily.
Go through the criteria one by one — yes, no or not sure — and take the list to your doctor or the study team. Kept in this browser only.
Male participants must meet at least one of the following conditions:
Has a fertile partner who agrees to follow guidance throughout the study period and for at least 6 months after the last dose of Nivolumab;
and
Female participants must meet at least one of the following conditions:
Preserved organ functions defined by:
Diagnosis of rare cancer (List I) confirmed by histopathological examination, with the possibility of including other types of rare tumors (incidence of less than 6 in every 100,000) after careful evaluation and approval by the study board.
List I:
Exclusion Criteria
Underlined terms in the criteria open these too. Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
PD-1, PD-L1 and CTLA-4 are proteins that act as brakes on the immune system. Checkpoint inhibitors, such as pembrolizumab or nivolumab, block them so the immune system can attack a cancer.
PD-L1 can also be measured in a tumour sample. Some scores count stained tumour cells only (TPS); others also count certain immune cells (CPS). The study names the score and the minimum it uses.
A scale of how much an illness limits everyday activity. For people being assessed to join a study, scores run from 0 (fully active) to 4; lower is more active.
Studies most often ask for 0–1 or 0–2. Your doctor gives the score; the WHO scale uses the same steps. The full scale also has 5, which records death.
The amount of disease can be tracked with a defined measurement, so the study can see whether it shrinks or grows. It might be a tumour measured on a scan or, in some blood cancers such as myeloma, a marker measured in blood or urine.
The criteria or the study team say which measurement counts — having no tumour visible on a scan does not by itself rule you out.
The standard rules for measuring tumours on CT or MRI scans, to tell whether a cancer is shrinking, stable or growing during treatment.
“Measurable disease per RECIST 1.1” usually means at least one tumour 10 mm or more at its longest on a CT scan, or a lymph node 15 mm or more across its short axis.
Ways of preventing pregnancy. “Highly effective” methods fail less than 1% of the time a year when used correctly — for example an IUD or an implant.
Criteria usually say which methods count and how long to keep using them after the last dose, sometimes for male participants too. Some studies accept a partner’s vasectomy if it was confirmed successful and that person is the participant’s only sexual partner.
The study doctor’s estimate of how long someone is likely to live. Criteria use it so that people can stay in the study long enough for it to answer its question.
The number of neutrophils, white blood cells that help fight infection, in a given amount of blood. Too few raises the risk of infection.
It is a count, not a percentage of the white cells. Limits are written in units that mean the same: ≥ 1.5 × 10⁹/L is ≥ 1,500 per mm³ (µL). Each lab has its own reference range.
The protein in red blood cells that carries oxygen. A low level is anaemia, which can cause tiredness and breathlessness. Measured in g/dL or g/L (9 g/dL is 90 g/L).
Blood cells that help blood clot. Too few raises the risk of bleeding and bruising. A usual adult range is about 150–400 × 10⁹/L (150,000–400,000 per µL); each lab has its own reference range.
A yellow substance made when red blood cells are broken down, which the liver clears. A high level can mean a problem with the liver or the bile ducts.
Criteria often allow more for people with Gilbert’s syndrome, a harmless inherited condition that raises bilirubin.
The top of the normal range for a blood test, as set by the laboratory that runs it. Each lab prints its own range next to your result.
“≤ 2.5 × ULN” means the result can be up to two and a half times that top value.
Two enzymes measured in a routine blood test of the liver. Higher levels can mean the liver is under strain or damaged. SGPT and SGOT are older names for ALT and AST.
Criteria usually give a limit as a multiple of the upper limit of normal (ULN), often higher when cancer has spread to the liver.
Cancer that has spread from where it began to other parts of the body. “Metastatic” cancer is cancer that has spread this way.
How quickly the kidneys clear creatinine, a waste product, from the blood. A study may estimate it from a blood test with age, weight and sex (often by the Cockcroft–Gault formula), or measure it using blood and urine collected over a set time. Given in mL/min; higher is better.
A condition in which the immune system attacks the body’s own tissues, such as rheumatoid arthritis, lupus, psoriasis, type 1 diabetes or inflammatory bowel disease.
Immunotherapy studies often leave out active autoimmune disease, and some name exceptions, such as thyroid disease on replacement hormone. Check the exceptions this study lists.
On an ECG, the QT interval is the time the heart’s lower chambers take to activate electrically and recover in each beat. QTc is that time adjusted for heart rate (QTcF by Fridericia’s formula, QTcB by Bazett’s). Some medicines lengthen it, and a long QTc can raise the risk of a dangerous heart rhythm.
The study may name a correction formula and a limit in milliseconds, often around 450–480.
Anti-inflammatory medicines such as prednisone, prednisolone and dexamethasone — not the anabolic steroids used for muscle.
Studies differ in what they allow: check which steroid medicines, routes (tablets, injections, creams, inhalers, eye drops) and doses this study accepts.
A weakened immune system. It can come from an illness, such as HIV or some blood cancers, or from medicines that turn the immune system down, for example after an organ transplant or for an autoimmune disease; steroids at higher doses count.
Read whether the line is about a condition or about medicines, and which medicines and doses it means.
The human immunodeficiency virus, which weakens the immune system.
Many studies now accept people whose HIV is controlled on treatment, judged by the viral load and the CD4 count. Check the limits this study sets.
PD-1, PD-L1 and checkpoint inhibitors
PD-1, PD-L1 and CTLA-4 are proteins that act as brakes on the immune system. Checkpoint inhibitors, such as pembrolizumab or nivolumab, block them so the immune system can attack a cancer.
PD-L1 can also be measured in a tumour sample. Some scores count stained tumour cells only (TPS); others also count certain immune cells (CPS). The study names the score and the minimum it uses.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
ECOG performance status
A scale of how much an illness limits everyday activity. For people being assessed to join a study, scores run from 0 (fully active) to 4; lower is more active.
Studies most often ask for 0–1 or 0–2. Your doctor gives the score; the WHO scale uses the same steps. The full scale also has 5, which records death.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Measurable disease
The amount of disease can be tracked with a defined measurement, so the study can see whether it shrinks or grows. It might be a tumour measured on a scan or, in some blood cancers such as myeloma, a marker measured in blood or urine.
The criteria or the study team say which measurement counts — having no tumour visible on a scan does not by itself rule you out.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
RECIST
The standard rules for measuring tumours on CT or MRI scans, to tell whether a cancer is shrinking, stable or growing during treatment.
“Measurable disease per RECIST 1.1” usually means at least one tumour 10 mm or more at its longest on a CT scan, or a lymph node 15 mm or more across its short axis.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Contraception
Ways of preventing pregnancy. “Highly effective” methods fail less than 1% of the time a year when used correctly — for example an IUD or an implant.
Criteria usually say which methods count and how long to keep using them after the last dose, sometimes for male participants too. Some studies accept a partner’s vasectomy if it was confirmed successful and that person is the participant’s only sexual partner.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Life expectancy
The study doctor’s estimate of how long someone is likely to live. Criteria use it so that people can stay in the study long enough for it to answer its question.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Absolute neutrophil count (ANC)
The number of neutrophils, white blood cells that help fight infection, in a given amount of blood. Too few raises the risk of infection.
It is a count, not a percentage of the white cells. Limits are written in units that mean the same: ≥ 1.5 × 10⁹/L is ≥ 1,500 per mm³ (µL). Each lab has its own reference range.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Hemoglobin (Hb)
The protein in red blood cells that carries oxygen. A low level is anaemia, which can cause tiredness and breathlessness. Measured in g/dL or g/L (9 g/dL is 90 g/L).
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Platelets
Blood cells that help blood clot. Too few raises the risk of bleeding and bruising. A usual adult range is about 150–400 × 10⁹/L (150,000–400,000 per µL); each lab has its own reference range.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Bilirubin
A yellow substance made when red blood cells are broken down, which the liver clears. A high level can mean a problem with the liver or the bile ducts.
Criteria often allow more for people with Gilbert’s syndrome, a harmless inherited condition that raises bilirubin.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
ULN (upper limit of normal)
The top of the normal range for a blood test, as set by the laboratory that runs it. Each lab prints its own range next to your result.
“≤ 2.5 × ULN” means the result can be up to two and a half times that top value.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
ALT and AST (liver enzymes)
Two enzymes measured in a routine blood test of the liver. Higher levels can mean the liver is under strain or damaged. SGPT and SGOT are older names for ALT and AST.
Criteria usually give a limit as a multiple of the upper limit of normal (ULN), often higher when cancer has spread to the liver.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Metastases
Cancer that has spread from where it began to other parts of the body. “Metastatic” cancer is cancer that has spread this way.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Creatinine clearance (CrCl)
How quickly the kidneys clear creatinine, a waste product, from the blood. A study may estimate it from a blood test with age, weight and sex (often by the Cockcroft–Gault formula), or measure it using blood and urine collected over a set time. Given in mL/min; higher is better.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Autoimmune disease
A condition in which the immune system attacks the body’s own tissues, such as rheumatoid arthritis, lupus, psoriasis, type 1 diabetes or inflammatory bowel disease.
Immunotherapy studies often leave out active autoimmune disease, and some name exceptions, such as thyroid disease on replacement hormone. Check the exceptions this study lists.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
QT and QTc
On an ECG, the QT interval is the time the heart’s lower chambers take to activate electrically and recover in each beat. QTc is that time adjusted for heart rate (QTcF by Fridericia’s formula, QTcB by Bazett’s). Some medicines lengthen it, and a long QTc can raise the risk of a dangerous heart rhythm.
The study may name a correction formula and a limit in milliseconds, often around 450–480.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Corticosteroids (steroids)
Anti-inflammatory medicines such as prednisone, prednisolone and dexamethasone — not the anabolic steroids used for muscle.
Studies differ in what they allow: check which steroid medicines, routes (tablets, injections, creams, inhalers, eye drops) and doses this study accepts.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Immunosuppression
A weakened immune system. It can come from an illness, such as HIV or some blood cancers, or from medicines that turn the immune system down, for example after an organ transplant or for an autoimmune disease; steroids at higher doses count.
Read whether the line is about a condition or about medicines, and which medicines and doses it means.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
HIV
The human immunodeficiency virus, which weakens the immune system.
Many studies now accept people whose HIV is controlled on treatment, judged by the viral load and the CD4 count. Check the limits this study sets.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Treatment will be administered with intravenous nivolumab at a dose of 480 mg every 4 weeks. Treatment will continue until limiting toxicity, disease progression, or for a maximum of 12 months as maintenance if the individual achieves stable disease, partial response, or complete response.
Drug: Nivolumab
The intervention consists of administering Nivolumab 480 mg intravenously every 4 weeks, with a +5 day window for postponement but not for advancement of treatment. Treatment will continue until limiting toxicity, disease progression, or for a maximum period of 12 months (13 cycles) as maintenance therapy, provided the patient maintains stable disease, a partial response, or a complete response. Patients who are off treatment for more than 56 days (2 cycles) due to Nivolumab-related toxicities or other clinical issues will be discontinued from the protocol. After 12 months of treatment or in the event of study discontinuation for any reason, patients will be followed by the research team via telephone every 60 days, with a +/- 7 day window, until death.
Primary Objective
Overall survival (in months) of patients with advanced or metastatic rare malignancies and CPS ≥ 10 following disease progression after prior treatments while receiving the anti-PD1 antibody Nivolumab.
Time frame: 2 years
Primary Endpoint
The primary outcome of the study is the disease control rate (DCR) based on imaging, considering the best response to treatment. A response rate of 5% will be considered non-promising, and a response rate of 25% will be considered promising. The study follows Simon's two-stage design, with type I error (alpha) set at 0.05 and type II error (beta) at 0.10. In the first stage, if at least 1 out of the first 9 participants achieves disease control (stable disease, partial response, or complete response), 16 additional participants will be recruited for the second stage. The study will be deemed positive if at least 3 out of 25 participants achieve disease control (partial response, complete response, or stable disease). A 10% drop-out rate (3 participants) is anticipated, bringing the maximum total recruitment to 28 participants.
Time frame: 2 years
Objective Response Rate (ORR)
Percentage of patients with a tumor size reduction, measured according to RECIST criteria.
Time frame: 2 years
Subgroup Analysis Based on PD-L1 Expression and CPS:
PD-L1 Expression: Proportion of patients showing PD-L1 positivity. CPS Subgroups: Proportion of patients with CPS between 10-20 and those with CPS \> 20.
Time frame: 2 years
Correlation of Clinical Outcomes with Biomarker Assessments
Microvesicle Analysis: Correlation between clinical outcomes and levels of circulating microvesicles. Serum Multiplex Panel: Correlation between clinical outcomes and serum biomarker levels (e.g., cytokines, chemokines), measured in concentration units (e.g., pg/mL).
Time frame: 2 years
Overall Survival (OS)
Time from treatment initiation to death from any cause, measured in months.
Time frame: 2 years
Progression-Free Survival (PFS)
Time from treatment initiation to disease progression or death, whichever occurs first, measured in months.
Time frame: 2 years
Plan to share: No — It has been decided not to share individual participant data (IPD) related to the study for several reasons. Protecting the privacy of participants is a priority. Sharing IPD may expose sensitive information that, even when de-identified, can be traced back to individuals. Furthermore, the complexity of the data makes sharing challenging without the risk of misunderstandings or misinterpretations, which could compromise the integrity of the research. Sharing IPD without the explicit consent of participants may violate ethical principles of respect and protection. There is also a need to comply with regulatory guidelines governing data sharing to avoid potential legal issues. Finally, the focus will be on disseminating aggregated results that can benefit the scientific community and the public without compromising individual privacy.
Started Jul 2024 (actual). Primary completion is estimated for Jul 2027, 36 months after the start.
Primary completion moved once since we started tracking on Sep 25, 2026: Jul 2026 → Jul 2027, on Oct 13, 2026.
Earlier changes are on the record history on ClinicalTrials.gov ↗
How these figures are worked out, and which studies are left out of them.
From the registry record's own update history. This site started tracking changes on Sep 25, 2026; for anything earlier, see the record history on ClinicalTrials.gov ↗
This study is active, not recruiting, as verified in Oct 2026. You cannot join it, but the record below documents what was studied.
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Studies of the drug tested here: Nivolumab
Instituto do Cancer do Estado de São Paulo