Glossary of terms

Glossary of terms
CSR report

Glossary of terms, to be read only in conjunction with this Q3 Report 2018.


100 points clinical response

Percentage of patients achieving a 100-point decrease in CDAI score during a clinical trial in CD patients


SEC filing submitted to the US Securities and Exchange 


American College of Rheumatology

ACR20 (ACR 20/50/70)

American College of Rheumatology 20% response rate signifies a 20% or greater improvement in the number of swollen and tender joints as well as a 20% or greater improvement in three out of five other disease-activity measures. ACR50 and ACR70 reflect the same, for 50% and 70% response rates, respectively


ADAMTS-5 is a key enzyme involved in cartilage breakdown (Larkin 2015)


American Depositary Share; Galapagos has a Level 3 ADS listed on Nasdaq with ticker symbol GLPG and CUSIP number 36315X101. One ADS is equivalent to one ordinary share in Galapagos NV


Dutch Authority for the Financial Markets


Condition in which the patient has an inadequate number of red blood cells to carry oxygen to the body’s tissues

Ankylosing spondylitis (AS)

AS is a systemic, chronic, and progressive spondyoloarthropathy primarily affecting the spine and sacroiliac joints, and progressing into severe inflammation that fuses the spine, leading to permanent painful stiffness of the back


Tumor necrosis factor. An anti-TNF drug acts by modulation of TNF

ARGS neoepitope

Byproduct of the breakdown of cartilage by aggrecanase, can be used as a biomarker for cartilage breakdown


Ankylosing Spondylitis Disease Activity Score, a composite score of symptoms such as back pain, duration of morning stiffness, and peripheral pain and swelling. We measured ASDAS scores in the TORTUGA trial with filgotinib in AS


Laboratory tests to determine characteristics

Atherogenic index

Total cholesterol over HDL ratio. Improvement of the atherogenic index may be a forecast of cardiovascular health

Atopic dermatitis (AtD)

Also known as atopic eczema, atopic dermatitis is a common pruritis inflammatory condition affecting the skin, which most frequently starts in childhood


ATS, the American Thoracic Society improves global health by advancing research, patient care, and public health in pulmonary disease, critical illness, and sleep disorders

Attrition rate

The historical success rate for drug discovery and development, based on publicly known development paths. Statistically seen, investment in at least 12 target-based programs is required to ensure that at least one of these will reach a Phase 3 study. Most new drug R&D programs are discontinued before reaching Phase 3 because they are not successful enough to be approved

Autotaxin (ATX)

An enzyme important for generating the signaling molecule lypophosphatidic acid (LPA). GLPG1690 targets autotaxin for IPF and SSc

BID dosing

Twice-daily dosing (bis in die)


Assessment of the amount of product candidate that reaches a body’s systemic circulation after (oral) administration


Substance used as an indicator of a biological process, particularly to determine whether a product candidate has a biological effect

Black & Scholes model

A mathematical description of financial markets and derivative investment instruments that is widely used in the pricing of European options and warrants

Bleomycin model

A preclinical model involving use of bleomycin (a cancer medication) to induce IPF symptoms

Bridging trial

Clinical trial performed to "bridge" or extrapolate one dataset to that for another situation, i.e. to extrapolate data from one population to another for the same drug candidate, or to move from IV to subcutaneous dosing


Crohn’s Disease Activity Index, evaluating patients on eight different factors, each of which has a pre-defined weight as a way to quantify the impact of CD

CDAI remission

In the FITZROY trial, the percentage of patients with CD who showed a reduction of CDAI score to <150


Crédit d’Impôt Recherche, or research credit. Under the CIR, the French government refunds up to 30% of the annual investment in French R&D operations, over a period of three years. Galapagos benefits from the CIR through its operations in Romainville, just outside Paris

Clinical proof-of-concept (PoC)

Point in the drug development process where the product candidate first shows efficacy in a therapeutic setting


A chemical substance, often a small molecule with drug-like properties

Contract research organization

Organization which provides drug discovery and development services


Any of a group of steroid hormones produced in the adrenal cortex or made synthetically. They have various metabolic functions and some are used to treat inflammation

Crohn’s disease (CD)

An IBD involving inflammation of the small and large intestines, leading to pain, bleeding, and ultimately in some cases surgical removal of parts of the bowel


C-reactive protein is a protein found in the blood, the levels of which rise in response to inflammation

Cutaneous lupus

Cutaneous lupus is a heterogeneous autoimmune skin disease that can present itself as an organ-specific disease (e.g., in the skin only) or as a systemic disease involving multiple organs

Cutaneous lupus erythematosus

Lupus affecting the skin. In this autoimmune disease, the body's immune system attacks healthy skin

Cystic fibrosis (CF)

A life-threatening genetic disease that affects approximately 80,000 people worldwide. Although the disease affects the entire body, difficulty breathing is the most serious symptom as a result of clogging of the airways due to mucus build-up and frequent lung infections


A category of small proteins which play important roles in signaling in processes in the body


Dactylitis is inflammation of a digit (either finger or toe) and is derived from the Greek word dactylos meaning finger. The affected fingers and/or toes swell up into a sausage shape and can become painful. Dactylitis was measured in the EQUATOR trial with filgotinib in psoriatic arthritis


Phase 2 program for filgotinib in RA. DARWIN 1 explored three doses, in twice-daily and once-daily administration, for up to 24 weeks in RA patients with insufficient response to methotrexate (MTX) and who remained on their stable background treatment with MTX. DARWIN 2 explored three once-daily doses for up to 24 weeks in RA patients with insufficient response to methotrexate (MTX) and who washed out of their treatment with MTX. DARWIN 1 and 2 were double-blind, placebo-controlled trials which recruited approximately 900 patients globally and for which results were reported in 2015. DARWIN 3 is a long term extension trial in which all patients are on 200 mg filgotinib, except for U.S. males who are on 100 mg. The week 156 results from DARWIN 3 were reported in 2019


DAS28 is an RA Disease Activity Score based on a calculation that uses tender and swollen joint counts of 28 defined joints, the physician’s global health assessment and a serum marker for inflammation, such as C-reactive protein. DAS28 (CRP) includes the C-reactive protein score calculation: scores range from 2.0 to 10.0, with scores below 2.6 being considered remission

Deep venous thrombosis (DVT)

The formation of one or more blood clots in one of the body's large veins, most commonly in the lower limbs. The blod clot can travel to the lung and cause a pulmonary embolism


All activities required to bring a new drug to the market. This includes preclinical and clinical development research, chemical and pharmaceutical development and regulatory filings of product candidates


Process by which new medicines are discovered and/or designed. At Galapagos, this is the department that oversees target and drug discovery research through to nomination of preclinical candidates


Addresses the disease itself, modifying the disease progression, not just the symptoms of the disease


Phase 3 program evaluating filgotinib in CD


DLCO (diffusion capacity of the lung for carbon monoxide) is the extent to which oxygen passes from the air sacs of the lungs into the blood. This is measured in IPF patients

Dose-range finding study

Phase 2 clinical study exploring the balance between efficacy and safety among various doses of treatment in patients. Results are used to determine doses for later studies


Term to characterize a clinical trial in which neither the physician nor the patient knows if the patient is taking placebo or the treatment being evaluated


Effectiveness for intended use


European Medicines Agency, in charge of European market authorization of new medications


A non-surgical procedure involving use of an endoscope to examine a person’s digestive tract


Inflammation of the tendons or ligaments; this is one of the key symptoms of psoriatic arthritis and was also measured in the EQUATOR trial with filgotinib


A Phase 2 trial with filgotinib in psoriatic arthritis patients


An approved drug (pirfenidone) for IPF, marketed by Roche


The U.S. Food and Drug Administration is an agency responsible for protecting and promoting public health and in charge of American market approval of new medications


Payment system where the service provider is paid a specific amount for each procedure or service performed


Forced expiratory volume measures how much air a person can exhale during a forced breath. The amount of air exhaled may be measured during the first (FEV1), second (FEV2), and/or third seconds (FEV3) of the forced breath

Fibrotic score

The Ashcroft fibrotic score involves measuring pulmonary fibrosis through examination of histopathology tissue


First-in-human clinical trial, usually conducted in healthy volunteers with the aim to assess the safety, tolerability and pharmacokinetics of the product candidate


Formerly known as GLPG0634. Small molecule selective JAK1 inhibitor, currently under review for approval in RA in the U.S., Europa and Japan. Filgotinib is partnered with Gilead for the development and commercialization of filgotinib in a number of diseases. Filgotinib currently is in Phase 3 trials in UC, CD and PsA, and Phase 2 trials in additional indications


Phase 3 program evaluating filgotinib in RA

Fistulizing CD

Fistulae are inflammatory tracts that most often occur between the distal colon and the perianal region. Fistulae are one of the most severe sequelae of luminal CD and the lifetime risk of occurrence is close to 50% of those with active CD


A double-blind, placebo controlled Phase 2 trial with filgotinib in 177 CD patients for up to 20 weeks. Full results were published in The Lancet in 2016


A double-blind, placebo-controlled exploratory Phase 2a trial with GLPG1690 in up to 24 IPF patients; topline results were reported in August 2017


Functional respiratory imaging is a technology which enhances 3D visualization and quantification of a patient’s airway and lung geometry


The Belgian market authority: Financial Services and Markets Authority, or Autoriteit voor Financiële Diensten en Markten


Full-time equivalent; a way to measure an employee’s involvement in a project. For example, an FTE of 1.0 means that the equivalent work of one full-time worker was used on the project

Futility analysis

Analysis of the likelihood of a trial to meet its primary endpoint, based on a subset of the total information to be gathered. The term 'futility' is used to refer to the low likelihood of a clinical trial to achieve its objectives. In particular, stopping a clinical trial when the interim results suggest that it is unlikely to achieve statistical significance can save resources that could be used on more promising research


Forced vital capacity is the amount of air which can be forcibly exhaled from the lungs after taking the deepest breath possible. FVC is used to help determine both the presence and severity of lung diseases such as IPF

G&A expenses

General & administrative expenses


A clinical candidate with undisclosed mode of action directed toward inflammation


Molecule number currently known as filgotinib


A GPR84 inhibitor fully proprietary to us. We initiated the PINTA patient trial with GLPG1205 in IPF


A novel drug targeting autotaxin, with potential application in IPF & SSc. Topline results from the Phase 2a FLORA trial were reported in August 2017. The ISABELA Phase 3 program was initiated in 2018 and the NOVESA Phase 2 trial in SSc was initiated in early 2019. Gilead retained the rights on GLPG1690 in IPF in 2019


GLPG1972/S201086, also referred to as GLPG1972, is a novel mode-of-action product candidate that is part of the OA collaboration with Servier. Galapagos and Servier have completed recruitment of the ROCCELLA global Phase 2b trial with GLPG1972/S201086


A clinical candidate with undisclosed novel mode of action. This compound is part of the CF collaboration with AbbVie but Galapagos regained rights outside of CF


A compound currently in Phase 1 with an undisclosed mode of action directed towards inflammation (IBD). GLPG3312 is a Toledo compound and the first one to enter Phase 1  


A compound currently in Phase 1 with an undisclosed mode of action directed toward inflammation


A compound currently in Phase 1 with an undisclosed mode of action. GLPG3970 is part of the Toledo target family


A compound with undisclosed mode of action currently in the preclincal phase directed toward metabolic diseases


A compound with undisclosed mode of action currently in the preclincal phase directed toward fibrosis


A compound with undisclosed mode of action currently in the preclincal phase directed toward inflammation


A compound with undisclosed mode of action currently in the preclincal phase directed toward inflammation


A compound with undisclosed mode of action currently in the preclincal phase directed toward inflammation

GPR84 inhibitor

Drug candidate aimed at inhibiting or blocking G-protein coupled receptor 84. GLPG1205 is a GPR84 inhibitor aimed at IPF


High-density lipoprotein. HDL scavenges and reduces low-density lipoprotein (LDL) which contributes to heart disease at high levels. High levels of HDL reduce the risk for heart disease, while low levels of HDL increase the risk of heart disease


A protein inside red blood cells that carries oxygen from the lungs to tissues and organs in the body and carries carbon dioxide back to the lungs


Microscopic examination of tissues for manifestations of a disease


Inflammatory Bowel Disease. This is a general term for an autoimmune disease affecting the bowel, including CD and UC. CD affects the small and large intestine, while UC affects the large intestine. Both diseases involve inflammation of the intestinal wall, leading to pain, bleeding, and ultimately, in some cases, surgical removal of part of the bowel


IL-17C has been shown to be distinct from other members of the IL-17 family of cytokines. IL-17C has been shown to be an important mediator in inflammatory skin diseases, and is the target of MOR106


Receiving/granting permission from/to another company or institution to use a brand name, patent, or other proprietary right, in exchange for a fee and/or royalty

In vitro

Studies performed with cells outside their natural context, for example in a laboratory

Inflammatory diseases

A large, unrelated group of disorders associated with abnormalities in inflammation

Inspiratory capacity

Total lung capacity or the amount of gas contained in the lung at the end of a maximal inhalation

Intellectual property

Creations of the mind that have commercial value and are protected or protectable, including by patents, trademarks or copyrights


Occurring between the different operations of a company

Investigational New Drug (IND) Application

United States Federal law requires a pharmaceutical company to obtain an exemption to ship an experimental drug across state lines, usually to clinical investigators, before a marketing application for the drug has been approved. The IND is the means by which the sponsor obtains this exemption, allowing them to perform clinical studies


Idiopathic pulmonary fibrosis. A chronic and ultimately fatal disease characterized by a progressive decline in lung function. Pulmonary fibrosis involves scarring of lung tissue and is the cause of shortness of breath. Fibrosis is usually associated with a poor prognosis. The term “idiopathic” is used because the cause of pulmonary fibrosis is still unknown


Phase 3 clinical program investigating GLPG1690 in IPF patients. The ISABELA Phase 3 program consists of two identically designed trials, ISABELA 1 and ISABELA 2, and will enroll a total of 1,500 IPF patients combined


Janus kinases (JAK) are critical components of signaling mechanisms utilized by a number of cytokines and growth factors, including those that are elevated in RA. Filgotinib is a selective JAK1 inhibitor


Low-density lipoprotein. LDL contributes to heart disease at high levels


Lipoproteins are substances made of protein and fat that carry cholesterol through your bloodstream. There are two main types of cholesterol: High-density lipoprotein (HDL), or "good" cholesterol and Low-density lipoprotein (LDL), or "bad" cholesterol

Liver enzymes

Inflamed or injured liver cells secrete higher than normal amounts of certain chemicals, including liver enzymes, into the bloodstream


Lysophosphatidic acid (LPA) is a signaling molecule involved in fibrosis


Type of white blood cell that is part of the immune system


Major adverse cardiovascular events; a composite endpoint frequently used in cardiovascular research


A Phase 2 semen analysis trial with filgotinib in male patients with CD or UC


Phase 2 semen analysis trial with filgotinib in male patients with RA, PsA, or AS

Membranous lupus nephritis

Membranous lupus nephritis is an inflammation of the kidneys caused by systemic lupus erythematosus and is characterized by the presence of subepithelial immune complex deposits seen on kidney biopsy


Japanese Ministry of Health, Labor and Welfare (MHLW), in charge of Japanese market authorization of new medications


Major achievement in a project or program; in our alliances, this is usually associated with a payment

Molecule collections

Chemical libraries, usually consisting of drug-like small molecules that are designed to interact with specific target classes. These collections can be screened against a target to generate initial “hits” in a drug discovery program


MOR106 acts on IL-17C, a novel antibody target discovered by Galapagos. In October 2019 Novartis, MorphoSys and Galapagos jointly announced the end of the clinical development program of MOR106 in patients with atopic dermatitis


Methotrexate; a first-line therapy for inflammatory diseases


New Drug Application


Type of immune system cell which is one of the first cell types to travel to the site of an infection in the body. Neutrophils are another type of white blood cell which fight infection by ingesting and killing microorganisms

NK cells

Natural killer cells, type of white blood cell with granules of enzymes which can attack tumors or viruses

Nonalcoholic steatohepatitis (NASH)

NASH is liver inflammation and damage caused by a buildup of fat in the liver. It is part of a group of conditions called nonalcoholic fatty liver disease


A Phase 2 trial to evaluate GLPG1690 in systemic sclerosis (SSc)


An approved drug (nintedanib) for IPF, marketed by Boehringer Ingelheim

Oral dosing

Administration of medicine by the mouth, either as a solution or solid (capsule, pill) form


Miniature organ produced from cells from a donor; organoids have all the phenotypic characteristics of the patient donor, making them useful tools for in vitro drug research

Osteoarthritis (OA)

The most common form of arthritis, usually occurring after middle age, marked by chronic breakdown of cartilage in the joints leading to pain, stiffness, and swelling


Contracting work to a third party


Phase 3 trials with filgotinib in psoriatic arthritis

Pharmacokinetics (PK)

Study of what a body does to a drug; the fate of a substance delivered to a body. This includes absorption, distribution to the tissues, metabolism and excretion. These processes determine the blood concentration of the drug and its metabolite(s) as a function of time from dosing

Phase 1

First stage of clinical testing of an investigational drug designed to assess the safety and tolerability, pharmacokinetics of a drug, usually performed in a small number of healthy human volunteers

Phase 2

Second stage of clinical testing, usually performed in no more than several hundred patients, in order to determine efficacy, tolerability and the dose to use

Phase 3

Large clinical trials, usually conducted in several hundred to several thousand patients to gain a definitive understanding of the efficacy and tolerability of the candidate treatment; serves as the principal basis for regulatory approval

Phenotypic screening

Phenotypic screening is a strategy used in drug discovery to identify molecules with the ability to alter a cell’s disease characteristics. Animal models and cell-based assays are both strategies used to identify these molecules. In contrast to target-based drug discovery, phenotypic screening does not rely on knowing the identity of the specific drug target or its hypothetical role in the disease. A key benefit this approach has over target-based screening, is its capacity to capture complex biological mechanisms that are not otherwise achievable


Phase 2 trial with GPR84 inhibitor GLPG1205 in IPF patients

Pivotal trials

Registrational clinical trials


A substance having no pharmacological effect but administered as a control in testing a biologically active preparation


Stage of drug research development, undertaken prior to the administration of the drug to humans. Consists of in vitro and in vivo screening, pharmacokinetics, toxicology, and chemical upscaling

Preclinical candidate (PCC)

A new molecule and potential drug that meets chemical and biological criteria to begin the development process

Product candidate

Substance that has satisfied the requirements of early preclinical testing and has been selected for development, starting with formal preclinical safety evaluation followed by clinical testing for the treatment of a certain disorder in humans

Proof-of-concept (POC)

A clinical trial in which first evidence for efficacy of a candidate drug is gathered. A Proof-of-Concept trial is usually with a small number of patients and for short duration to get a first impression of drug activity

Proof-of-concept study

Phase 2 patient study in which activity as well as safety in patients is evaluated, usually for a new mechanism of action


Extreme itching, as observed in AtD patients

Psoriatic arthritis (PsA)

Psoriatic arthritis or PsA is an inflammatory form of arthritis, affecting up to 30% of psoriasis patients. Psoriatic arthritis can cause swelling, stiffness and pain in and around the joints, and cause nail changes and overall fatigue

Pulmonary embolisms

A blockage in one of the pulmonary arteries in the lungs

QD dosing

Once-daily dosing (qd from the Latin quaque die)

R&D operations

Research and development operations; unit responsible for discovery and developing new product candidates for internal pipeline or as part of risk/reward sharing alliances with partners

Rheumatoid arthritis (RA)

A chronic, systemic inflammatory disease that causes joint inflammation, and usually leads to cartilage destruction, bone erosion and disability


Global Phase 2b trial, together with our collaboration partner Servier, evaluating GLPG1972/S201086 (GLPG1972) in osteoarthritis (OA)


Method usually applied at the beginning of a drug discovery campaign, where a target is tested in a biochemical assay against a series of small molecules or antibodies to obtain an initial set of “hits” that show activity against the target. These hits are then further tested or optimized


Securities Exchange Commission in the US


Phase 3 program evaluating filgotinib in UC patients

Service operations

Business unit primarily focused on delivering products and conducting fee-for-service work for clients. Our service operations included the BioFocus and Argenta business units, which were both sold in April 2014 to Charles River Laboratories

SES-CD scores

Simple endoscopic score for CD, involving review of five pre-defined bowel segments, assigning values from 0 (unaffected) to 3 (highly affected)

Sjögren’s syndrome

Sjögren’s Syndrome is a systemic inflammatory disease which can be felt throughout the body, often resulting in chronic dryness of the eyes and mouth

S&M expenses

Sales and marketing expenses

Small bowel CD (SBCD)

CD causes chronic inflammation and erosion of the intestines. It can affect different regions of gastrointestinal tract including the stomach and small and large intestines. While isolated SBCD is an uncommon presentation of CD, involvement of some portion of the small bowel, particularly the ileum, is common


About 20% of patients with psoriatic arthritis will develop spinal involvement, which is called psoriatic spondylitis. Inflammation of the spine can lead to complete fusion, as in AS, or affect only certain areas such as the lower back or neck. We measured spondylitis in the EQUATOR trial with filgotinib in psoriatic arthritis

Systemic sclerosis (SSc)

Systemic sclerosis (SSc) or scleroderma is an autoimmune disease. One of the most visible manifestations is hardening of the skin. In diffuse cutaneous SSc, which has one of the highest mortality rates among rheumatic diseases, fibrosis occurs in multiple organs, such as the lung


Proteïn that has been shown to play a role in a disease process and that forms the basis of a therapeutic intervention or discovery of a medicine

Target discovery

Identification and validation of proteins that have been shown to play a role in a disease process

Technology access fee

License payment made in return for access to specific technology (e.g. compound or virus collections)


Tendinitis is inflammation or irritation of a tendon, the thick fibrous cords that attach muscle to bone. The condition causes pain and tenderness just outside a joint. We measured tendinitis in the EQUATOR trial with filgotinib in psoriatic arthritis


Toledo is a code name for a target family with a novel, undisclosed mode of action. GLPG3312 is the first of the Toledo compounds for which a Phase 1-trial has been initiated early 2019

Topical corticosteroids

Corticosteroids which are administered through the skin using an ointment


Phase 2 trial with filgotinib in patients with ankylosing spondylitis. In 2018, we and Gilead reported that TORTUGA met its primary endpoint

Ulcerative colitis (UC)

UC is an IBD causing chronic inflammation of the lining of the colon and rectum (unlike CD with inflammation throughout the gastrointestinal tract)


Uveitis is the term that refers to inflammation inside the eye. This inflammation can be caused by infection, autoimmune reaction, or by conditions confined primarily to the eye

Venous thrombotic events

When a blood clot breaks loose and travels in the blood, this is called a venous thromboembolism (VTE). The abbreviation DVT/PE refers to a VTE where a deep vein thrombosis (DVT) has moved to the lungs (PE or pulmonary embolism)