V: Various

ATC group V for modelers: the catch-all letter, effective half-life for radiopharmaceuticals, and notes held at V03, V08 and V10.
Modified

September 22, 2026

ATC group V is the catch-all letter of the classification [1]. The notes below cover three of its nine level 2 codes: therapeutic radiopharmaceuticals, reversal agents and contrast media.

In 2002 Anton Bom and colleagues at Organon described a cyclodextrin that reverses rocuronium block by encapsulating the relaxant itself rather than acting on a receptor [2].

Table 1: ATC V level 2 codes
Level 2 code Description In plain terms Example drug
V01 Allergens extracts for allergy testing and desensitization Grass pollen allergen extract (V01AA02) / house dust mite allergen extract (V01AA03)
V03 All other therapeutic products catch-all: antidotes, chelators, medical gases Naloxone (V03AB15) / acetylcysteine (V03AB23)
V04 Diagnostic agents Tuberculin (V04CF01) / 13C-urea (V04CX05)
V06 General nutrients No substance to name: enteral and parenteral nutrition products are classified at group level only (V06A, V06B, V06C, V06DA, V06DB, V06DD, V06DE, V06DF, V06DX carry no level 5 substances). The only level 5 entries in the whole group are glucose (V06DC01) and fructose (V06DC02).
V07 All other non-therapeutic products non-medicines: dressings, solvents, disinfectants, cosmetics No substance to name, and no level 5 codes anywhere in the group: every subgroup stops at level 4, e.g. solvents and diluting agents (V07AB), blood transfusion auxiliary products (V07AC), technical disinfectants (V07AV).
V08 Contrast media injected agents that make scans visible Iohexol (V08AB02) / gadobutrol (V08CA09)
V09 Diagnostic radiopharmaceuticals radioactive tracers injected to image the body Fludeoxyglucose (18F) (V09IX04) / technetium (99mTc) medronic acid (V09BA02)
V10 Therapeutic radiopharmaceuticals radioactive drugs given to treat disease Sodium iodide (131I) (V10XA01) / lutetium (177Lu) vipivotide tetraxetan (V10XX05)
V20 Surgical dressings No substance to name: V20 has no subdivisions at all. The classification stops at the level 2 group code V20 (surgical dressings), with no level 3, 4 or 5 entries.

Modeling notes

Endpoint. For therapeutic radiopharmaceuticals the driver is a physical quantity, the absorbed dose in Gy to tumor and organs at risk, reconstructed from serial post-infusion imaging rather than from a plasma concentration-time curve [3]. In 177Lu-PSMA-617 therapy the lesion dose-response relationship is real but only moderate, Spearman rho about -0.3 [4].

Decay is not clearance (V09, V10). Imaging measures activity, which falls by radioactive decay and by biological clearance together, so what is fitted is an effective half-life [5]. With few imaging time points the fit is unstable, and population fitting stabilizes the time-integrated activity [6].

References

[1]
WHO Collaborating Centre for Drug Statistics Methodology. ATC/DDD index 2026 2026.
[2]
Bom A, Bradley M, Cameron K, Clark JK, Egmond J van, Feilden H, et al. A novel concept of reversing neuromuscular block: Chemical encapsulation of rocuronium bromide by a cyclodextrin-based synthetic host. Angewandte Chemie International Edition 2002;41:265–70. https://doi.org/10.1002/1521-3773(20020118)41:2<265::AID-ANIE265>3.0.CO;2-Q.
[3]
Hebert K, Santoro L, Monnier M, Castan F, Berkane I, Assénat E, et al. Absorbed dose-response relationship in patients with gastroenteropancreatic neuroendocrine tumors treated with [177Lu]lu-DOTATATE: One step closer to personalized medicine. Journal of Nuclear Medicine 2024;65:923–30. https://doi.org/10.2967/jnumed.123.267023.
[4]
Grkovski M et al. Lesion absorbed dose-response relationship in patients with metastatic castration-resistant prostate cancer undergoing [177Lu]lu-PSMA-617 radiopharmaceutical therapy. Journal of Nuclear Medicine 2025;66:1622–30. https://doi.org/10.2967/jnumed.125.270170.
[5]
Oliveira CV et al. Analysis of residence time, effective half-life, and internal dosimetry before radioiodine therapy. Journal of Nuclear Medicine Technology 2022;50:233–9. https://doi.org/10.2967/jnmt.121.263502.
[6]
Hardiansyah D, Riana A, Kletting P, Zaid NRR, Eiber M, Pawiro SA, et al. A population-based method to determine the time-integrated activity in molecular radiotherapy. EJNMMI Physics 2021;8:82. https://doi.org/10.1186/s40658-021-00427-x.