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Glossary
A plain-English guide to the words Baxtra uses across pathogen science, drug discovery, clinical trials, regulation, containment, manufacturing and statistics. The terms are grouped by theme so that a reader can find the vocabulary around a question rather than search one long list.
Why put a glossary on a pharmaceutical site at all. Because a page about a medicine can be technically accurate and still exclude the people expected to read it. Patients, families, investigators, partners and members of the public should not have to know the difference between a surrogate endpoint and an endpoint before they can understand what is being said. This page is a starting point, not a substitute for a protocol, a label or a regulator's document.
01 / Pathogens
Disease and pathogen terms
These are the words used to describe an infectious agent, the disease it can cause, and the way it moves between hosts. They describe biology, not a prediction about whether a Baxtra programme will succeed.
Plain-English definitions necessarily lose some precision. Where a definition here conflicts with a legal, regulatory, protocol or biosafety definition, the regulatory or other governing definition applies. The relevant source document wins over this page.
90Terms in this glossary
7Theme groups
1–3Sentences per definition
31 AugData and wording reviewed 2026
| Term | Plain-English definition |
|---|---|
| Antigen | A substance the immune system can recognise and respond to. It may be part of a pathogen, or a material made by an infected cell. |
| Case fatality rate | The proportion of diagnosed cases that result in death, usually expressed as a percentage. It changes with case finding, time of follow-up and the population studied. |
| Encephalitis | Inflammation of the brain. Infection is one possible cause, and symptoms can include confusion, seizures or changes in consciousness. |
| Incubation period | The time between exposure to an infectious agent and the first symptoms. It is a range, not a reliable countdown for every person. |
| Pathogen | An infectious organism or agent that can cause disease. Viruses, bacteria, fungi and prions are examples. |
| Prion | An infectious form of a misfolded protein rather than a virus or bacterium. Prions can cause progressive nervous-system diseases. |
| Reservoir host | An animal or population in which a pathogen normally persists and from which it can spread. A reservoir host may show little or no illness. |
| Spillover | The transfer of a pathogen from its usual host or environment into a new host species. Spillover does not always lead to sustained transmission in the new species. |
| Transmission | The passage of a pathogen from one host, source or environment to another. The route may be respiratory, contact, sexual, vector-borne, food-borne or another route. |
| Vector | An animal, often an insect or tick, that carries a pathogen between hosts. The vector is not necessarily harmed by carrying it. |
| Viral haemorrhagic fever | A serious illness caused by certain viruses that can damage blood vessels and disrupt clotting. Bleeding may occur, but it is not present in every case. |
| Virulence | The degree of harm a pathogen causes in an infected host. It is different from transmissibility, which describes how readily an agent spreads. |
| Zoonosis | An infection that can pass naturally between animals and people. Some zoonoses are occasional spillovers; others can spread between people after introduction. |
02 / Molecules
Drug discovery and modality terms
A modality is the broad kind of intervention being developed. The terms below cover what a candidate is made to do, how the body handles it, and how researchers test whether it reaches its intended biological target.
| Term | Plain-English definition |
|---|---|
| Antisense oligonucleotide | A short designed strand of nucleic acid that binds a specific RNA sequence. Binding can change how that RNA is read or removed by the cell. |
| Bioavailability | The fraction of a dose that reaches the bloodstream in a form that can have an effect. It is often lower after oral dosing than after direct intravenous dosing. |
| Brain-to-plasma ratio | A comparison of a substance's measured concentration in brain tissue with its concentration in plasma. It is a distribution measure, not proof of benefit. |
| Efflux pump | A protein that moves substances out of a cell. In bacteria, efflux pumps can reduce the amount of an antibacterial drug that remains inside the cell. |
| Fusion inhibitor | A drug designed to stop a virus from joining its membrane with a host-cell membrane. Without that step, entry into the cell may be prevented. |
| Half-life | The time it takes for the amount or concentration of a substance in the body to fall by half under a stated model. It helps describe dosing intervals, but it can vary between people and tissues. |
| Host-directed therapy | An intervention aimed at a process in the infected person's cells or tissues rather than directly at the pathogen. It may seek to limit harmful host responses or make cells less permissive. |
| Mechanism of action | The biological chain of events through which a candidate is intended to produce its effect. Early descriptions are hypotheses that are tested and may be revised. |
| Monoclonal antibody | A laboratory-made antibody designed to bind one particular target. A treatment can use one antibody or a combination of antibodies with different targets. |
| Pharmacodynamics | The study of what a drug does to the body, including its biological effects and relationship to dose or concentration. |
| Pharmacokinetics | The study of what the body does to a drug: absorption, distribution, metabolism and excretion. It helps determine dose and timing. |
| Polymerase inhibitor | A drug designed to block a polymerase, an enzyme that copies genetic material. Viruses often need their polymerase to make more copies of themselves. |
| Small molecule | A relatively low-molecular-weight chemical compound that can often enter cells and bind a molecular target. It is a description of size and chemistry, not a judgement about quality. |
03 / People and protocols
Clinical trial terms
Clinical research uses controlled language because small differences can change what a result means. These definitions are deliberately short; the protocol, investigator brochure and consent materials remain the authoritative documents for a particular study.
| Term | Plain-English definition |
|---|---|
| Adverse event | Any unwanted medical occurrence in a participant after they join a study, whether or not it was caused by the study intervention. |
| Blinding | Keeping one or more groups in a study unaware of which intervention a participant received. It is used to reduce the influence of expectations on care or assessment. |
| Cohort | A group of participants who share a planned feature, such as a dose level or schedule. A study may enrol several cohorts in sequence. |
| Dose-limiting toxicity | A side effect or laboratory finding serious enough, under the study rules, to limit further dose increases. The protocol defines what counts and during which period it is assessed. |
| Dose escalation | A planned move from a lower dose to a higher dose after review of safety and other specified information. Escalation can stop, pause or move down. |
| Endpoint | A defined measurement used to assess a study question, such as a symptom, laboratory value, imaging result or survival measure. An endpoint should be specified before the result is known. |
| First-in-human | The first study in people of a particular candidate or formulation. It follows laboratory and other preclinical work but still carries uncertainty. |
| Informed consent | A person's voluntary agreement to take part after receiving understandable information about the study, its risks, alternatives and practical requirements. Consent can be withdrawn. |
| Institutional review board | An independent committee that reviews research involving people, including its risks, safeguards and consent process. It is often called an IRB. |
| Multiple ascending dose | A study design in which participants receive repeated doses, with different cohorts receiving planned increasing dose levels. It is often shortened to MAD. |
| Placebo | An intervention made to resemble the study intervention but without its active drug ingredient. It helps separate effects of the intervention from other changes, where its use is appropriate. |
| Randomisation | Assigning participants to study groups using a chance-based method. It helps make groups comparable, although it cannot guarantee identical groups. |
| Single ascending dose | A study design in which each participant receives one planned dose, with different cohorts receiving increasing doses. It is often shortened to SAD. |
| Serious adverse event | An adverse event that meets a defined seriousness criterion, such as death, a life-threatening event, hospitalisation or a lasting disability. Serious does not automatically mean caused by the intervention. |
| Surrogate endpoint | A measurement used as a substitute for a direct clinical outcome because it is expected to predict it. A surrogate can be useful but may not capture the outcome that matters most to patients. |
04 / Oversight
Regulatory terms
Regulatory terms describe the route by which a sponsor asks an authority to review an investigational medicine or device. A route is not a guarantee of approval, and a designation is not the same thing as a marketing authorisation.
| Term | Plain-English definition |
|---|---|
| 505(b)(1) | A US New Drug Application route based on the sponsor's own full reports of safety and effectiveness. It is a submission pathway, not an approval. |
| 510(k) | A US device submission showing that a new device is substantially equivalent to a legally marketed predicate device. The FDA's clearance decision is specific to the submission. |
| Common technical document | An internationally used structure for organising quality, non-clinical and clinical information in a medicine submission. It makes a large dossier easier for reviewers to navigate. |
| Expedited review | A regulatory process intended to shorten or prioritise review when the legal criteria are met. It does not remove the requirement to provide the evidence the authority needs. |
| FDA Animal Rule | A US pathway that can allow certain effectiveness questions to be supported by well-controlled animal studies when human trials would be unethical or infeasible, alongside required human safety information. The rule is in 21 CFR 314 Subpart I. |
| Good clinical practice | International ethical and scientific standards for designing, conducting, recording and reporting studies involving people. It protects participants and supports credible data. |
| Good laboratory practice | Quality standards for the way certain non-clinical laboratory studies are planned, performed, recorded, reported and archived. |
| Good manufacturing practice | Requirements intended to ensure that medicines are consistently made and controlled to the quality standards appropriate for their use. GMP covers people, premises, processes, records and testing. |
| ICH | The International Council for Harmonisation, which brings regulators and the pharmaceutical industry together to develop harmonised technical guidelines for medicines. |
| Investigational new drug application | A US submission to the FDA that allows a sponsor to request permission to begin or continue clinical investigation of an unapproved medicine. It contains information on the candidate, manufacturing, non-clinical work and proposed study. |
| Orphan designation | A regulatory designation for a medicine intended for a rare disease or condition when the applicable legal criteria are met. It may provide incentives, but it is not approval. |
| Priority review voucher | A regulatory incentive that can give an eligible sponsor a faster review for a later product submission, subject to the governing programme and its conditions. Receiving or transferring a voucher does not establish that a product is safe or effective. |
| Regulatory authority | A public body with legal responsibility for overseeing medicines, devices, trials or related activities. Its powers and definitions depend on the country and product. |
05 / Controls
Biosafety and containment terms
Containment is a set of physical, procedural and behavioural controls used to keep hazardous biological material in the work area and protect people and the environment. The classification of a facility is not a substitute for a task-specific risk assessment.
| Term | Plain-English definition |
|---|---|
| Airlock | A controlled space between areas with different access or pressure conditions. Doors are managed so that people and material do not create an uncontrolled open route. |
| Biosafety level | A graded set of containment practices, equipment and facility controls matched to biological risk. The levels are commonly called BSL-1 through BSL-4. |
| Chemical shower | A decontamination station that uses a chemical agent to treat a person, suit or material as required by the facility procedure. It is not an ordinary washroom shower. |
| Decontamination | The process of removing, inactivating or destroying hazardous contamination so that a person, surface, item or waste stream can be handled safely under the applicable procedure. |
| Dual use research of concern | Research that can be used for beneficial purposes but could also be misused to cause harm. It requires careful review of the work, its information and its safeguards. |
| HEPA filtration | High-efficiency particulate air filtration that removes a very high proportion of particles from an air stream. Its performance depends on correct installation, testing and maintenance. |
| Positive-pressure suit | A fully enclosed protective suit supplied with clean air at pressure higher than the surrounding room. The pressure helps prevent room air entering through a small breach. |
| Primary containment | The first barrier between hazardous material and the worker or room, such as a sealed vessel, safety cabinet or protective suit. |
| Risk group | A classification of an agent based on factors such as its ability to cause disease, spread and the availability of prevention or treatment. Risk group is one input to a biosafety assessment, not the whole assessment. |
| Secondary containment | The facility-level barrier around the primary work area, including rooms, ventilation, access controls and waste systems. It limits release beyond the immediate work zone. |
| Select agent | A biological agent or toxin designated by law as having the potential to pose a severe threat to public, animal or plant health. Work with one is subject to specific security and oversight requirements. |
| Stop-work authority | The authority of any worker to halt an activity when they believe it is unsafe or outside the approved procedure. It should not depend on seniority or permission from the person leading the work. |
| Two-person rule | A control requiring two authorised people to be present for specified work or access. It provides an independent check and means one person is not the sole observer of a critical step. |
Baxtra's public statement on the August 2026 containment event confirms only that an event occurred, that its own staff found it, that work stopped, an independent review is open and authorities were notified. It names no programme, suite, material, quantities, dates or individuals, and states there is no identified risk outside the facility. Read the statement.
06 / Making and checking
Manufacturing and quality terms
Quality systems turn a laboratory process into a controlled process that can be repeated, investigated and audited. A clean record is useful, but it is not evidence that nothing went wrong; it is evidence that the process was recorded and reviewed.
| Term | Plain-English definition |
|---|---|
| Batch record | The controlled record of how one batch was made, tested and handled. It includes the steps performed, materials used, results and required reviews. |
| CAPA | Corrective and preventive action: a structured process for fixing a problem, addressing its cause and reducing the chance that it will recur. A CAPA is not complete merely because an action was assigned. |
| Change control | The formal review and approval process for a proposed change to a product, process, facility, method or document. The review considers impact, evidence, training and records. |
| Cleanroom | A controlled room in which airborne particles, temperature, humidity and pressure are managed for a defined use. Clean does not mean sterile. |
| Deviation | A departure from an approved instruction, expected result or established process. It is recorded, assessed for impact and investigated according to the quality system. |
| Lot | A defined quantity of material made under conditions expected to be uniform. In many settings, lot and batch are used similarly, but the governing record defines the term. |
| Quality management system | The linked policies, processes, responsibilities, records and checks used to control quality. It includes how an organisation learns from errors rather than only how it prevents them. |
| Release testing | Testing performed before a batch is accepted for its intended next use. The tests and acceptance criteria are set in advance and do not turn a failed result into a pass. |
| Sterility assurance | The collection of controls and evidence used to reduce the risk that a product or process is contaminated with viable microorganisms. It is a system, not a single test. |
| Traceability | The ability to follow the history, location, materials, decisions and records connected to a product or process. It makes a reconstruction possible when a question is raised later. |
| Validation | Documented evidence that a process, method or system can consistently produce a result that meets its intended requirements. Validation is planned and justified rather than assumed from one successful run. |
07 / Reading results
Statistics terms
Statistics cannot remove uncertainty from a study. They give researchers a disciplined way to describe the observations, quantify some uncertainty and distinguish a pre-specified question from a result found after looking at the data.
| Term | Plain-English definition |
|---|---|
| Confidence interval | A range calculated from sample data that describes uncertainty around an estimate. The method and confidence level matter; it is not a guarantee that the true value lies in the range. |
| Hazard ratio | A comparison of the rate at which an event happens over time between two groups. It is not the same as a risk ratio, and its interpretation depends on the analysis model. |
| Intention to treat | An analysis approach that keeps participants in the groups to which they were randomised, usually regardless of whether they completed the assigned intervention. It preserves the benefit of randomisation but requires careful handling of missing data. |
| Kaplan-Meier | A method for estimating the proportion of participants who have not yet experienced an event over time. It can account for participants whose follow-up ends before the event occurs. |
| Mean | The arithmetic average: add the values and divide by the number of values. A few very high or low values can pull the mean away from what is typical. |
| Median | The middle value after observations are ordered. Half the observations are above it and half below it, making it less affected by extreme values than the mean. |
| Missing data | Information that was planned for collection but is not available. The reason data are missing can affect the result, so it should not be treated as a neutral inconvenience. |
| p-value | A measure, under a specified statistical model, of how unusual data at least this extreme would be if the null hypothesis were true. It is not the probability that the null hypothesis is true. |
| Power | The probability that a study will detect a specified effect at a chosen significance threshold if that effect truly exists. Power depends on sample size, variability, effect size and the analysis plan. |
| Standard deviation | A measure of how spread out observations are around their mean. A larger standard deviation means more variation in the measured values. |
| Type I error | Concluding that an effect exists when it does not under the stated null hypothesis. The significance threshold is one way a study controls the planned rate of this error. |
| Type II error | Failing to detect a specified effect when it exists. The probability of avoiding this error is related to statistical power. |
A statistically clear result can still be too small to matter to a patient, and a clinically important difference can be missed by a study that is too small or too noisy. Read the estimate, its uncertainty, the protocol and the limitations together.
Keep reading
Put the terms back in their setting
A definition is the beginning of understanding, not the whole account. The science, clinical trials, containment standards and cleared documents show how these words are used in practice. Every investigational medicine on this site remains investigational; none has been approved by a regulatory authority.