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 228
Breast cancer 94
Obesity 86
Prostate cancer 73
Colorectal cancer 69
Ovarian cancer 66
Non-small cell lung cancer metastatic 66
Crohn’s disease 61
Type 2 diabetes mellitus 54
Rheumatoid arthritis 54
Triple negative breast cancer 52
Hormone receptor positive HER2 negative breast cancer 52
Asthma 51
Acute myeloid leukaemia 50
Squamous cell carcinoma of head and neck 50
Chronic kidney disease 49
Neoplasm 48
Colorectal cancer metastatic 47
Hepatocellular carcinoma 47
Systemic lupus erythematosus 40
Colitis ulcerative 40
Multiple sclerosis 39
Overweight 39
Dementia Alzheimer’s type 39
Gastric cancer 38
Myelodysplastic syndrome 37
Parkinson’s disease 37
HER2 positive breast cancer 37
Glioblastoma 37
Atrial fibrillation 34
Bladder cancer 34
Chronic obstructive pulmonary disease 33
Ischaemic stroke 33
Prostate cancer metastatic 33
Myasthenia gravis 32
Renal transplant 31
Type 1 diabetes mellitus 31
Head and neck cancer 31
Endometrial cancer 31
Malignant melanoma 31
Non-small cell lung cancer stage IV 31
Diffuse large B-cell lymphoma 31
Breast cancer metastatic 31
HIV infection 30
Dermatitis atopic 28
Cholangiocarcinoma 28
Coronary artery disease 28
Plasma cell myeloma 28
Pulmonary arterial hypertension 28
Neoplasm malignant 27
Rectal cancer 27
Renal cell carcinoma 26
Pancreatic carcinoma 26
Schizophrenia 26
Duchenne muscular dystrophy 25
Non-small cell lung cancer stage III 25
Follicular lymphoma 25
COVID-19 25
Migraine 24
Hormone receptor positive breast cancer 24
Idiopathic pulmonary fibrosis 24
Non-small cell lung cancer stage IIIB 24
Sepsis 24
Chronic lymphocytic leukaemia 24
Soft tissue sarcoma 24
Mantle cell lymphoma 23
Small cell lung cancer extensive stage 23
Colon cancer 23
Fallopian tube cancer 23
Influenza 22
Small cell lung cancer 21
Interstitial lung disease 21
Acute myocardial infarction 21
Oesophageal adenocarcinoma 21
Amyotrophic lateral sclerosis 21
Chronic rhinosinusitis with nasal polyps 20
Cystic fibrosis 20
Glioma 20
Myelofibrosis 19
Neuroblastoma 19
B-cell lymphoma 19
Sickle cell disease 19
Major depression 19
Procedural pain 19
Axial spondyloarthritis 18
Osteoarthritis 18
Breast cancer female 17
Critical illness 17
Acute kidney injury 17
Hereditary angioedema 17
Relapsing-remitting multiple sclerosis 16
Acute coronary syndrome 16
IgA nephropathy 16
Psoriasis 16
Gastrooesophageal cancer 16
Ewing’s sarcoma 16
Cardiac failure 16
Vitiligo 16
Transitional cell carcinoma 15
Giant cell arteritis 15

Diseases starting with h

  • 1

    H1N1 influenza

    H1N1 influenza, commonly known as swine flu, is a respiratory infection caused by a type A influenza virus that can spread quickly from person to person and cause symptoms ranging from mild flu-like illness to severe complications.

  • 0

    Habitual abortion

    Habitual abortion is a condition where a woman experiences multiple consecutive pregnancy losses, typically defined as three or more spontaneous miscarriages. While this reproductive problem is relatively uncommon, affecting about 1% of couples, it can cause significant emotional distress and frustration for those trying to build a family.

  • 0

    Haematological infection

    Infections are among the most serious complications for people with blood disorders, particularly those undergoing treatment or stem cell transplantation. Understanding your infection risk and how to protect yourself is crucial for managing your health.

  • 8

    Haematological malignancy

    Haematological malignancies are cancers that affect the blood, bone marrow, lymph nodes, and the lymphatic system, representing the fifth most common cancer group in economically developed regions.

  • 2

    Haemodialysis

    Haemodialysis is a life-saving treatment that filters wastes and excess water from your blood when your kidneys are no longer able to do this work.

  • 1

    Haemodynamic instability

    Haemodynamic instability is a serious condition in which the body’s circulatory system cannot maintain adequate blood flow and pressure to deliver enough oxygen and nutrients to vital organs.

  • 0

    Haemofiltration

    Haemofiltration is a medical procedure used to clean the blood when the kidneys cannot work properly, particularly in intensive care units where patients need continuous support for acute kidney problems.

  • 0

    Haemoglobinuria

    Haemoglobinuria is a condition where the oxygen-carrying protein from red blood cells appears in the urine, often turning it a dark reddish or brown color. This happens when red blood cells break down inside blood vessels, releasing their contents into the bloodstream, which the kidneys then filter into the urine.

  • 0

    Haemolytic uraemic syndrome

    Haemolytic uraemic syndrome is a serious condition that damages small blood vessels, most commonly affecting the kidneys and often occurring after bacterial infection, particularly in young children.

  • 6

    Haemophagocytic lymphohistiocytosis

    Haemophagocytic lymphohistiocytosis is a rare and life-threatening condition where the immune system attacks the body’s own tissues instead of defending it against disease. Without prompt diagnosis and treatment, this severe inflammatory syndrome can lead to organ failure and death within months, but early intervention and proper care can save lives.

  • 1

    Haemophilia

    Haemophilia is a rare inherited blood disorder in which blood does not clot properly, causing prolonged bleeding from injuries and sometimes internal bleeding that can damage joints and organs.

  • 0

    Haemophilia A with anti factor VIII

    Haemophilia A with anti factor VIII represents one of the most challenging complications in treating this inherited bleeding disorder. When the body creates antibodies against the very treatment meant to help, managing bleeding episodes becomes significantly more difficult.

  • 1

    Haemophilia A without inhibitors

    Haemophilia A is a hereditary bleeding disorder where blood does not clot properly due to a lack of clotting factor VIII. With proper treatment and care, people with this condition can lead full and active lives.

  • 0

    Haemophilia B with anti factor IX

    When the body’s immune system creates antibodies against the very treatment meant to help, managing haemophilia B becomes significantly more challenging.

  • 0

    Haemophilia B without inhibitors

    Haemophilia B, also known as Christmas disease, is an inherited bleeding disorder caused by a deficiency in clotting factor IX. While it predominantly affects males due to its X-linked inheritance pattern, effective treatment allows most people with this condition to lead normal, active lives.

  • 0

    Haemoptysis

    Haemoptysis, the coughing up of blood from the lungs or airways, can range from a small amount of blood-streaked mucus to a life-threatening medical emergency requiring immediate attention.

  • 0

    Haemorrhage

    Haemorrhage is a loss of blood from damaged blood vessels that can occur inside or outside your body. While minor bleeding like bruises may resolve on their own, severe haemorrhage is a medical emergency that can lead to organ failure or death if not treated promptly.

  • 1

    Haemorrhage intracranial

    Intracranial haemorrhage is a type of stroke that causes bleeding inside the skull or brain tissue, preventing oxygen from reaching your brain. This life-threatening medical emergency requires immediate treatment to prevent permanent brain damage or death.

  • 1

    Haemorrhage prophylaxis

    Preventing excessive bleeding during and after medical procedures or childbirth can save lives and reduce serious complications. Understanding when and how to prevent hemorrhage helps healthcare teams protect patients from life-threatening blood loss.

  • 1

    Haemorrhagic stroke

    A haemorrhagic stroke is a life-threatening medical emergency that occurs when a blood vessel in the brain ruptures and bleeds. This less common but more dangerous type of stroke requires immediate treatment, as every second counts in preventing permanent brain damage or death.

  • 1

    Haemorrhoids

    Haemorrhoids are swollen veins in the lower part of the rectum and around the anus that can cause pain, itching, and bleeding. This common condition affects about half of all people over age 50, but many cases can be managed at home with simple lifestyle changes and treatments.

  • 2

    Hairy cell leukaemia

    Hairy cell leukaemia is a rare type of cancer that grows slowly in the blood and bone marrow, named after the unusual “hairy” appearance of the affected cells when viewed under a microscope.

  • 0

    Hairy cell leukaemia recurrent

    Hairy cell leukaemia is a rare type of blood cancer that often comes back after treatment, but patients can achieve further periods of remission with repeated therapy.

  • 0

    Hand dermatitis

    Hand dermatitis is one of the most common skin conditions, affecting as many as 1 in 10 people and causing red, itchy, and painful skin on the hands that can seriously impact daily life and work.

  • 0

    Hand fracture

    A hand fracture is a break in one or more of the bones that make up your hand. These injuries can happen during falls, sports activities, car accidents, or when striking a hard object, and they require proper care to heal correctly and restore full hand function.

  • 31

    Head and neck cancer

    Head and neck cancer includes several different types of cancers that develop in areas such as the mouth, throat, voice box, nose, and sinuses. Most begin in the thin, flat cells that line these moist surfaces, and many are linked to tobacco use, alcohol consumption, and certain viral infections.

  • 3

    Head and neck cancer metastatic

    When cancer from the head and neck region spreads to other parts of the body, it becomes a complex disease requiring specialized care and understanding of how it behaves differently than cancer that stays in one place.

  • 1

    Head and neck cancer stage III

    Stage III head and neck cancer represents a significant turning point in the disease, where the tumor has grown larger or begun to involve nearby lymph nodes, requiring more complex treatment approaches that often combine multiple therapies.

  • 1

    Head and neck cancer stage IV

    Stage IV head and neck cancer represents the most advanced form of this disease, where cancer has grown extensively, spread to lymph nodes, or reached distant parts of the body. Understanding this stage and available treatment options is an important step in managing your care.

  • 1

    Head injury

    A head injury can range from a minor bump to a life-threatening condition affecting your brain. Most head injuries are mild and temporary, but some can cause serious complications like bleeding inside the skull or permanent brain damage.

  • 2

    Heart disease congenital

    Congenital heart disease affects the structure of the heart from birth, making it the most common type of birth defect. While some heart problems are mild and require little treatment, others are life-threatening and demand immediate medical attention. Thanks to advances in diagnosis and treatment, most children born with these conditions now survive into adulthood.

  • 11

    Heart failure with preserved ejection fraction

    Heart failure with preserved ejection fraction is a complex condition affecting millions of people worldwide, where the heart’s pumping ability appears normal but the muscle becomes stiff and cannot relax properly to fill with blood, leading to symptoms that significantly impact daily life.

  • 12

    Heart failure with reduced ejection fraction

    Heart failure with reduced ejection fraction is a condition where the heart’s main pumping chamber cannot push blood forward as effectively as it should, causing blood to back up into the lungs and body, leading to shortness of breath and swelling.

  • 6

    Heart transplant

    A heart transplant is a major surgical procedure that replaces a failing heart with a healthy donor heart, offering hope to people whose hearts can no longer pump blood effectively despite other treatments.

  • 1

    Henoch-Schonlein purpura

    Henoch-Schonlein purpura is a condition that causes inflammation of small blood vessels, leading to a distinctive rash and other symptoms. While it most commonly affects children between ages 2 and 10, it can occur at any age and usually resolves on its own within a few weeks.

  • 1

    Heparin resistance

    Heparin resistance is a challenging condition that occurs when unusually large doses of heparin are needed to achieve the desired level of blood thinning. This problem has gained increased attention in intensive care units, particularly during the COVID-19 pandemic, when many critically ill patients required anticoagulation but failed to respond to standard heparin doses.

  • 0

    Hepatic adenoma

    Hepatic adenoma is a rare, non-cancerous liver tumor that primarily affects women, especially those who use birth control pills. Although benign, these tumors carry risks of internal bleeding and, in rare cases, can transform into cancer.

  • 1

    Hepatic angiosarcoma

    Hepatic angiosarcoma is a rare but highly aggressive cancer that develops in the blood vessels of the liver. Though it accounts for less than 2% of all liver cancers, it is the third most common primary liver cancer and the most common malignant tumor arising from the liver’s blood vessels in adults.

  • 4

    Hepatic cancer

    Hepatic cancer, also known as liver cancer, is a serious disease where cancer cells grow in the liver—one of the body’s largest and most vital organs. Most cases occur in people who already have long-term liver damage or disease.

  • 8

    Hepatic cirrhosis

    Hepatic cirrhosis is a serious condition where the liver becomes permanently scarred and damaged over many years. While it cannot be cured or reversed, understanding the condition and getting proper treatment can help slow its progression and manage complications, allowing many people to live well for years.

  • 2

    Hepatic encephalopathy

    Hepatic encephalopathy is a serious brain disorder that occurs when a damaged liver can no longer remove toxins from the blood, causing confusion, personality changes, and impaired thinking that can progress to coma or death without treatment.

  • 3

    Hepatic fibrosis

    Hepatic fibrosis is a condition where excessive scar tissue builds up in the liver, replacing healthy tissue that normally helps your body function. While early stages can sometimes be reversed, understanding this condition and its causes is crucial for protecting your liver health.

  • 0

    Hepatic neoplasm

    Hepatic neoplasms are tumors that develop in the liver, one of the body’s largest and most vital organs. Understanding these growths, their causes, and available treatments can help patients and their families navigate this serious condition with greater confidence.

  • 1

    Hepatitis alcoholic

    Alcoholic hepatitis is a serious liver condition caused by heavy alcohol use that leads to inflammation and damage of liver cells. While mild cases may improve with proper care, severe cases can be life-threatening, with high mortality rates even with treatment.

  • 6

    Hepatitis B

    Hepatitis B is a liver infection caused by a virus that can spread through contact with infected blood or body fluids. While some people recover quickly, others develop a lifelong infection that can lead to serious liver damage if not properly monitored and managed.

  • 11

    Hepatitis D

    Hepatitis D is a serious liver infection that can only affect people who already have hepatitis B. It is considered the most severe form of viral hepatitis and can lead to rapid liver damage, but it can be prevented by getting vaccinated against hepatitis B.

  • 0

    Hepato-lenticular degeneration

    Hepato-lenticular degeneration, also known as Wilson disease, is a rare inherited disorder where the body cannot properly eliminate copper, leading to its dangerous accumulation in the liver, brain, and other organs. While this condition can be life-threatening if untreated, early diagnosis and lifelong management can allow most people to live normal, healthy lives.

  • 2

    Hepatobiliary cancer

    Hepatobiliary cancers are serious conditions that affect the liver, pancreas, gallbladder, and bile ducts—organs responsible for producing, storing, and transporting bile, a fluid essential for digestion.

  • 0

    Hepatobiliary disease

    Hepatobiliary disease includes a range of disorders affecting the liver, gallbladder, and bile ducts—organs that work together to help digest food, remove waste, and keep your body healthy. These conditions can vary from minor problems to serious diseases that may require lifelong care.

  • 2

    Hepatoblastoma

    Hepatoblastoma is a very rare type of liver cancer that primarily affects babies and young children, most commonly before their third birthday. While the diagnosis can be frightening for families, advances in treatment combining chemotherapy and surgery have dramatically improved outcomes, with many children achieving complete recovery.

  • 47

    Hepatocellular carcinoma

    Hepatocellular carcinoma is the most common type of liver cancer, affecting thousands of people each year. While it is a serious condition that often develops in people with long-term liver damage, early detection and advances in treatment offer important opportunities for improving outcomes.

  • 1

    Hepatorenal syndrome

    Hepatorenal syndrome is a life-threatening condition where the kidneys suddenly fail in people with severe liver disease. Despite normal kidney structure, the organs stop working because narrowed blood vessels prevent adequate blood flow, creating a medical emergency that requires immediate attention.

  • 1

    Hepatotoxicity

    Hepatotoxicity is liver damage caused by exposure to harmful substances such as medications, chemicals, herbal products, or alcohol. This condition can range from mild symptoms detected only through blood tests to severe, life-threatening liver failure requiring urgent medical attention.

  • 1

    HER2 mutant non-small cell lung cancer

    HER2 mutant non-small cell lung cancer is a rare form of lung cancer caused by specific genetic changes in the HER2 protein. Though it affects only a small percentage of lung cancer patients, recent advances in targeted treatments are offering new hope for those diagnosed with this condition.

  • 11

    HER2 negative breast cancer

    HER2-negative breast cancer is the most common type of breast cancer, affecting about 4 out of 5 people diagnosed with the disease. Understanding your HER2 status helps your healthcare team choose the right treatment plan for you.

  • 1

    HER2 positive biliary tract cancer

    Recent advances in targeted therapies have opened new doors for patients with HER2 positive biliary tract cancer, a rare and difficult-to-treat disease that has long been known for its poor prognosis.

  • 38

    HER2 positive breast cancer

    HER2-positive breast cancer was once considered one of the most aggressive forms of the disease, but thanks to major advances in targeted treatments, it has become one of the most successfully treated types of breast cancer.

  • 5

    HER2 positive gastric cancer

    HER2 positive gastric cancer is a distinct type of stomach cancer that produces high levels of a protein called HER2, making it grow faster than other types. This discovery has led to new targeted treatments that can help patients live longer.

  • 1

    HER2 protein overexpression

    HER2 protein overexpression occurs when cells make too much of a specific protein that controls cell growth, leading to faster cancer development in several types of tumors, particularly breast and stomach cancers.

  • 17

    Hereditary angioedema

    Hereditary angioedema (HAE) is a rare genetic condition that causes sudden, severe swelling in different parts of the body. Though unpredictable and potentially life-threatening, advances in treatment now offer hope for people living with this challenging disorder.