Explore popular diseases in clinical trials

Check which popular diseases are currently being frequently studied.

See also our rare diseases glossary and drug database.

Starting by letter

To open the diseases glossary, select a letter from the list below.

Most popular diseases

The list below features the most popular diseases currently involved in ongoing clinical trials.

Disease trials
Non-small cell lung cancer 240
Breast cancer 99
Obesity 92
Prostate cancer 77
Colorectal cancer 69
Ovarian cancer 68
Crohn’s disease 67
Non-small cell lung cancer metastatic 64
Rheumatoid arthritis 55
Squamous cell carcinoma of head and neck 54
Triple negative breast cancer 54
Chronic kidney disease 50
Asthma 50
Hepatocellular carcinoma 47
Neoplasm 47
Acute myeloid leukaemia 47
Colorectal cancer metastatic 46
Overweight 45
Multiple sclerosis 43
Colitis ulcerative 40
Parkinson’s disease 40
HER2 positive breast cancer 39
Gastric cancer 38
Myelodysplastic syndrome 38
Dementia Alzheimer’s type 37
Glioblastoma 36
Bladder cancer 34
Atrial fibrillation 34
Prostate cancer metastatic 34
Renal transplant 33
Ischaemic stroke 33
Diffuse large B-cell lymphoma 32
Chronic obstructive pulmonary disease 32
Head and neck cancer 32
Non-small cell lung cancer stage IV 31
Breast cancer metastatic 30
Coronary artery disease 29
Myasthenia gravis 29
Malignant melanoma 29
Endometrial cancer 28
Cholangiocarcinoma 28
Rectal cancer 27
Pulmonary arterial hypertension 27
Dermatitis atopic 27
Idiopathic pulmonary fibrosis 27
Soft tissue sarcoma 26
Non-small cell lung cancer stage III 26
Plasma cell myeloma 25
Pancreatic carcinoma 25
Small cell lung cancer extensive stage 25
Sepsis 25
Renal cell carcinoma 25
Schizophrenia 24
COVID-19 24
Duchenne muscular dystrophy 24
Non-small cell lung cancer stage IIIB 24
Follicular lymphoma 24
Hormone receptor positive breast cancer 24
Fallopian tube cancer 23
Amyotrophic lateral sclerosis 23
Mantle cell lymphoma 23
Influenza 22
Neoplasm malignant 22
Chronic lymphocytic leukaemia 21
Acute myocardial infarction 21
Major depression 21
Small cell lung cancer 21
Sickle cell disease 21
Interstitial lung disease 21
Cystic fibrosis 21
Breast cancer female 20
Osteoarthritis 20
Glioma 20
Neuroblastoma 20
Chronic rhinosinusitis with nasal polyps 20
Oesophageal adenocarcinoma 20
Myelofibrosis 19
B-cell lymphoma 19
Critical illness 18
Procedural pain 18
Acute kidney injury 18
Psoriasis 18
Axial spondyloarthritis 18
Acute coronary syndrome 17
Vitiligo 17
Hereditary angioedema 17
Relapsing-remitting multiple sclerosis 17
Ewing’s sarcoma 17
IgA nephropathy 17
Gastrooesophageal cancer 16
Juvenile idiopathic arthritis 16
Cardiac failure 16
Uveal melanoma 16
Chronic hepatitis B 16
Allogenic stem cell transplantation 15
Giant cell arteritis 15
Chronic spontaneous urticaria 15
Cardiac arrest 15
Septic shock 14
Malignant melanoma stage III 14

All diseases

  • 0

    Pancreatic failure

    When the pancreas cannot produce enough digestive enzymes, the body struggles to absorb nutrients from food, leading to serious health consequences that require careful management and treatment.

  • 2

    Pancreatic fistula

    A pancreatic fistula is an abnormal connection that forms when the pancreas develops a leak, allowing digestive fluids to drain where they shouldn’t. This complication most often occurs after surgery but can also result from injury or severe inflammation of the pancreas.

  • 1

    Pancreatic neoplasm

    Pancreatic neoplasm is a serious health condition that forms in the tissues of the pancreas, an organ vital for digestion and blood sugar control. Most people don’t show signs in early stages, making this disease particularly challenging to detect and treat.

  • 1

    Pancreatic neuroendocrine tumour

    Pancreatic neuroendocrine tumours are rare growths that start in special hormone-making cells inside the pancreas. Though uncommon, accounting for only 1 to 2% of pancreatic cancers, many of these tumours grow slowly and can be treated effectively, offering better outcomes than other types of pancreatic cancer.

  • 0

    Pancreatic neuroendocrine tumour metastatic

    Pancreatic neuroendocrine tumours that have spread to other parts of the body represent a challenging form of cancer, yet they often grow more slowly than other pancreatic cancers and can be managed for extended periods with appropriate treatment.

  • 1

    Pancreaticoduodenectomy

    Pancreaticoduodenectomy, commonly known as the Whipple procedure, is a major surgical operation that removes parts of the pancreas and nearby organs to treat cancer and other serious conditions in the digestive system.

  • 5

    Pancreatitis acute

    Acute pancreatitis is a sudden inflammation of the pancreas that can range from mild discomfort to a serious medical emergency. While most people recover within a week, understanding the symptoms, causes, and treatment options is essential for anyone experiencing severe abdominal pain.

  • 1

    Pancreatitis chronic

    Chronic pancreatitis is a long-lasting condition where the pancreas becomes inflamed, scarred, and progressively damaged over time, leading to permanent changes that affect digestion and blood sugar control.

  • 1

    Pancreatitis relapsing

    Relapsing pancreatitis is a condition where people experience repeated episodes of pancreatic inflammation that can progressively worsen over time, causing severe pain and potentially leading to permanent damage to this vital digestive organ.

  • 1

    Papillary cystadenoma lymphomatosum

    Papillary cystadenoma lymphomatosum is a non-cancerous growth that most commonly develops in the salivary glands near the ear. Despite its complex name, this slow-growing tumor is the second most frequent benign tumor of these glands and rarely causes serious problems.

  • 1

    Papillary serous endometrial carcinoma

    Papillary serous endometrial carcinoma is a rare but aggressive form of uterine cancer that requires early detection and comprehensive treatment. Though it accounts for only about 10% of endometrial cancer cases, it is responsible for approximately 40% of deaths from this disease.

  • 2

    Papillary thyroid cancer

    Papillary thyroid cancer is the most common form of thyroid cancer, accounting for about 80 to 85 percent of all cases. While hearing a cancer diagnosis can be frightening, this type of thyroid cancer typically grows very slowly and has an excellent prognosis, with most patients achieving successful treatment outcomes.

  • 0

    Papilloma viral infection

    Human papillomavirus (HPV) is the most common viral infection spread through intimate contact, affecting most sexually active people at some point in their lives. While many infections clear on their own, some types can cause warts or lead to serious cancers years later.

  • 1

    Papulopustular rosacea

    Papulopustular rosacea is a chronic inflammatory skin condition that causes pus-filled bumps and persistent redness on the face, often mistaken for acne but requiring different treatment approaches.

  • 0

    Paraesthesia

    Paraesthesia is the sensation of tingling, numbness, burning, or “pins and needles” that can affect any part of your body. While everyone experiences these feelings from time to time, understanding when they are harmless and when they require medical attention can help you protect your health.

  • 1

    Paraganglion neoplasm

    Paraganglion neoplasm, commonly called paraganglioma, is a rare tumor that forms near major blood vessels and nerve pathways, most often in the neck, head, abdomen, or chest. While most of these tumors are not cancer, they can produce hormones that cause serious health problems like high blood pressure, rapid heartbeat, and severe headaches.

  • 1

    Paraneoplastic neurological syndrome

    Paraneoplastic neurological syndromes are rare conditions that occur when the body’s immune system, while fighting cancer, mistakenly attacks the nervous system, causing symptoms that often appear before the cancer itself is even discovered.

  • 0

    Paresis

    Paresis is a condition in which muscle movement is weakened, but unlike paralysis, you still have some control over the affected muscles. It usually occurs due to nerve damage and can affect different parts of your body, from a single limb to all four limbs.

  • 39

    Parkinson’s disease

    Parkinson’s disease is a progressive brain disorder that affects movement and many other aspects of daily life. While there is currently no cure, understanding the condition and available treatments can help people manage symptoms and maintain quality of life for many years.

  • 10

    Paroxysmal nocturnal haemoglobinuria

    Paroxysmal nocturnal haemoglobinuria (PNH) is a rare blood disorder where the body’s immune system mistakenly attacks and destroys its own red blood cells, leading to serious complications including anaemia, blood clots, and kidney problems.

  • 1

    Partial lipodystrophy

    Partial lipodystrophy is a rare condition where the body loses fat tissue from specific areas such as the arms, legs, and buttocks, while fat may accumulate in other regions like the face, neck, and abdomen. This abnormal distribution of fat can lead to serious metabolic complications including diabetes, high triglycerides, and fatty liver disease.

  • 2

    Partial seizures

    Partial seizures affect a specific area of the brain and are the most common type of seizures in people with epilepsy. While these seizures can be frightening, most can be controlled with proper treatment and lifestyle adjustments.

  • 1

    Patent ductus arteriosus

    Patent ductus arteriosus is a heart condition where a blood vessel that should close shortly after birth remains open, allowing extra blood to flow to the lungs and putting strain on the heart.

  • 0

    Pathogen resistance

    Antimicrobial resistance occurs when harmful germs evolve to survive the drugs designed to kill them, turning once-treatable infections into serious, sometimes impossible-to-cure health threats that affect millions of people worldwide.

  • 2

    Pelizaeus-Merzbacher disease

    Pelizaeus-Merzbacher disease is a rare inherited condition that affects the brain and spinal cord, primarily occurring in males. The disease disrupts the body’s ability to produce enough myelin, the protective coating around nerves, leading to problems with movement, balance, and development that worsen over time.

  • 0

    Pelvic venous thrombosis

    Pelvic venous thrombosis occurs when a blood clot forms in one of the veins located in the pelvic region, blocking blood flow and potentially causing serious health complications if left untreated.

  • 0

    Pemphigoid

    Pemphigoid is a rare blistering condition that mainly affects people over 60 years old. While it can be serious and last for years, proper treatment helps control the symptoms and allows the skin to heal, though it may take time and patience.

  • 1

    Pemphigus

    Pemphigus is a group of rare autoimmune diseases that cause painful blisters and sores to form on the skin and inside the mouth. While there is no cure, treatments can help control symptoms and allow many people to manage this lifelong condition.

  • 4

    Penile cancer

    Penile cancer is a rare disease where abnormal cells in the penis grow out of control, forming a tumor. While uncommon in developed countries like the United States, early detection and treatment can often cure this disease, making it crucial to recognize symptoms and seek medical help promptly.

  • 3

    Penile squamous cell carcinoma

    Penile squamous cell carcinoma is a rare but serious form of cancer that affects the penis, representing about 95% of all penile cancers. While uncommon in developed countries, early detection and modern treatment approaches can often lead to successful outcomes and preserve quality of life.

  • 0

    Peptostreptococcus infection

    Peptostreptococcus infections are caused by bacteria that normally live harmlessly in the human body but can turn dangerous when conditions allow them to spread and multiply beyond their usual areas.

  • 3

    Periarthritis

    Periarthritis is a condition that causes pain and stiffness in joints, most commonly affecting the shoulder, where it is often called “frozen shoulder” or adhesive capsulitis.

  • 1

    Pericarditis

    Pericarditis is inflammation of the protective sac surrounding your heart, causing sharp chest pain that often improves when sitting forward. While it can feel alarming, most people recover within weeks with proper treatment, though some experience recurring episodes that require ongoing care.

  • 0

    Perinatal depression

    Perinatal depression affects approximately 1 in 7 people during pregnancy or within the first year after childbirth, yet up to half of all cases remain undiagnosed. This common mood disorder is more than just “baby blues” and requires proper recognition and treatment to protect both parent and child.

  • 2

    Perineal injury

    Perineal injury during childbirth is very common, affecting up to 9 in every 10 first-time mothers who have a vaginal birth. While most tears are minor and heal quickly, understanding what happens, how to care for yourself, and when to seek help can make your recovery smoother and less stressful.

  • 1

    Periodontitis

    Periodontitis is a serious gum infection that damages the soft tissue around teeth and can destroy the bone that supports them, potentially leading to tooth loss. While common and affecting millions of people worldwide, this condition is largely preventable with proper care and treatable when caught early.

  • 5

    Peripheral arterial occlusive disease

    Peripheral arterial occlusive disease is a common condition where narrowed arteries reduce blood flow to the legs, usually due to plaque buildup. While many people experience leg pain when walking, others have no symptoms at all—yet the condition signals important health risks that require attention.

  • 2

    Peripheral artery angioplasty

    When arteries in your legs or arms become narrowed by fatty deposits, blood struggles to reach your muscles and tissues. Peripheral artery angioplasty is a procedure that can widen these blocked vessels, helping blood flow more easily and reducing pain or other symptoms.

  • 1

    Peripheral artery restenosis

    Peripheral artery restenosis is a complication that occurs when arteries that were previously treated with procedures like angioplasty or stenting become narrowed again, limiting blood flow to the legs or other parts of the body.

  • 1

    Peripheral artery stenosis

    Peripheral artery stenosis, commonly known as peripheral artery disease (PAD), affects millions of people worldwide when arteries in the limbs become narrowed or blocked, restricting blood flow and potentially causing pain, difficulty walking, and serious complications if left untreated.

  • 1

    Peripheral artery thrombosis

    Peripheral artery thrombosis occurs when a blood clot forms in arteries that carry blood to the arms or legs, blocking or restricting blood flow and potentially causing serious complications if left untreated.

  • 0

    Peripheral ischaemia

    Peripheral ischaemia, commonly known as peripheral artery disease (PAD), is a condition where narrowed arteries reduce blood flow to the limbs—usually the legs—causing pain during activity and other serious complications.

  • 1

    Peripheral primitive neuroectodermal tumour of soft tissue

    Peripheral primitive neuroectodermal tumour of soft tissue is a rare and highly aggressive cancer that develops from embryonic nerve cells in tissues outside the central nervous system, most commonly affecting young people and requiring intensive combined treatment.

  • 0

    Peripheral sensorimotor neuropathy

    Peripheral sensorimotor neuropathy is a condition that affects nerves throughout your body, causing problems with both movement and sensation. This nerve damage can develop slowly over years or appear suddenly within hours to days, impacting your ability to feel, move, and maintain balance.

  • 1

    Peripheral spondyloarthritis

    Peripheral spondyloarthritis is a form of inflammatory arthritis that primarily affects the joints in the arms and legs, rather than the spine, causing pain, swelling, and stiffness that can significantly impact daily life.

  • 6

    Peripheral T-cell lymphoma unspecified

    Peripheral T-cell lymphoma, not otherwise specified (PTCL-NOS) is a rare and aggressive blood cancer that develops from mature white blood cells called T-cells, affecting the lymphatic system and potentially spreading throughout the body.

  • 0

    Peritoneal abscess

    A peritoneal abscess is a serious infection where pus accumulates in the abdomen, requiring prompt medical attention. Early detection and proper treatment with antibiotics and drainage can prevent life-threatening complications like sepsis and organ failure.

  • 6

    Peritoneal cancer index

    The peritoneal cancer index is a scoring system that helps doctors measure how much cancer has spread throughout the lining of the abdomen, guiding treatment decisions and predicting how likely surgery is to remove all visible tumors.

  • 1

    Peritoneal carcinoma metastatic

    Peritoneal carcinoma metastatic occurs when cancer from another organ spreads to the peritoneum, the membrane lining the abdominal cavity. While this condition is serious and typically represents advanced disease, modern treatments combining surgery and specialized chemotherapy are helping patients live longer and improve their quality of life.

  • 1

    Peritoneal dialysis

    Peritoneal dialysis is a treatment that allows people with kidney failure to clean their blood at home, using the natural lining of their abdomen as a filter instead of relying on a machine outside the body.

  • 2

    Peritoneal mesothelioma malignant

    Peritoneal mesothelioma is a rare and aggressive cancer that affects the tissue lining the abdomen. While there is no cure, advances in treatment combining surgery and specialized chemotherapy have transformed survival from less than a year to several years for many patients.

  • 2

    Peritoneal neoplasm

    Peritoneal neoplasm is a rare cancer that affects the peritoneum, a thin membrane lining the abdomen and covering the organs inside it. Most people don’t notice symptoms until the disease has progressed to a later stage, making early detection challenging. Treatment typically involves surgery combined with specialized chemotherapy, offering hope for improved survival and quality of life.

  • 0

    Peritoneal sarcoma

    Peritoneal sarcoma is a rare type of cancer that develops when sarcoma tumors appear in or spread to the peritoneum, the thin lining inside the abdomen that covers organs and produces lubricating fluid.

  • 3

    Peritonitis

    Peritonitis is a serious inflammation of the tissue lining the inside of your belly that requires immediate medical attention and can become life-threatening without prompt treatment.

  • 3

    Persistent corneal epithelial defect

    When the clear outer layer of the eye fails to heal properly after an injury, it can lead to a challenging condition that requires prompt attention to prevent serious complications including infection, scarring, and vision loss.

  • 0

    Persistent depressive disorder

    Persistent depressive disorder is a long-lasting form of depression where feelings of sadness and emptiness persist for years rather than weeks or months, affecting daily life, relationships, and the ability to find joy even during happy moments.

  • 0

    Perthes disease

    Perthes disease is a childhood hip condition where blood supply to the ball-shaped head of the thigh bone is temporarily interrupted, causing the bone to break down and then gradually heal over several years.

  • 1

    Pertussis

    Pertussis, commonly called whooping cough, is a highly contagious respiratory infection that can cause severe coughing fits lasting for weeks or even months. While it affects people of all ages, it poses the greatest danger to babies, who may experience life-threatening complications.

  • 0

    Petit mal epilepsy

    Petit mal epilepsy, now known as absence seizures, causes brief episodes where a person suddenly stares blankly and loses awareness for just a few seconds, often going unnoticed by observers and sometimes mistaken for daydreaming.

  • 2

    Peyronie’s disease

    Peyronie’s disease is a condition that causes the penis to curve or bend abnormally during erections due to scar tissue formation beneath the skin. This can lead to pain, difficulty with sexual activity, and emotional distress for many men.