De Simone Formulation UK: Timeline, Strains, Availability
Reference page (UK). For public education. Not medical advice.
De Simone Formulation UK: Timeline, Strains, Availability
VSL#3® is a registered trademark of VSL Pharmaceuticals Inc. and Actial S.r.l. Vivomixx® is a registered trademark of Mendes SA. Visbiome® is a registered trademark of ExeGi Pharma. CDS22-formula is manufactured by EOS2021 S.r.l. These are independent companies and are not affiliated with each other.
Probiotic.co.uk and CDS22-formula are not affiliated with, endorsed by, sponsored by or connected to the holders of the VSL#3, Vivomixx or Visbiome trademarks. Those brand names are referred to on this page for identification and historical reference only. CDS22-formula is a separate product sold in competition with them. Nothing on this page should be read as a claim that CDS22-formula is, continues to be, or is a version of any of those branded products.
This page is published by a commercial party. Probiotic.co.uk distributes CDS22-formula and is not a neutral party. Statements below are attributed to the published sources that made them and are linked in section 10. Readers should consult those primary sources directly rather than rely on this summary, and should obtain current specifications from each manufacturer before drawing any conclusion about any product.
The De Simone Formulation (DSF) is an 8-strain probiotic mixture developed by Professor Claudio De Simone. ECCO states that until 2016 this formulation was sold under the brand name VSL#3, and that after 2016 the product sold as VSL#3 no longer contains the De Simone Formulation [1]. Readers should read that statement in full and obtain current specifications directly from each manufacturer.
The De Simone Formulation (also called DSF) is a specific high-potency 8-strain probiotic formulation developed by Professor Claudio De Simone. ECCO states that until 2016 DSF was sold under the VSL#3 brand name, that after 2016 the product sold as VSL#3 no longer contains DSF, and that the VSL#3 references in its 2017 guidelines should be read as relating to DSF [1]. In separate US proceedings, a Maryland jury found in 2018 that claims of equivalence between the post-2016 US VSL#3 product and the earlier formulation were false and misleading under the Lanham Act, affirmed by the Fourth Circuit in February 2021 [2]. This page sets out a source-based definition, a strain identity table with deposit codes, a timeline drawn from published sources, and a practical verification method based on the strain list rather than the brand name.
1) What is the De Simone Formulation?
The De Simone Formulation (DSF) is a probiotic formulation and manufacturing approach developed by Professor Claudio De Simone. In published literature and clinical discussions, DSF is described as a multi-strain, high-potency probiotic mixture. ECCO states it was sold as VSL#3 prior to 2016 [1].
The 8 strains: historic naming and current UK label
The left column shows the species naming used in pre-2016 literature. The right column reproduces the strain names and NCIMB deposit codes stated on the current UK CDS22-formula label. This comparison is provided for reference and does not independently establish identity or clinical equivalence.
| Genus | Species name used in pre-2016 literature | Current UK CDS22-formula label |
|---|---|---|
| Streptococcus | Streptococcus thermophilus | S. thermophilus NCIMB 30438 |
| Bifidobacterium | Bifidobacterium breve | B. breve NCIMB 30441 |
| Bifidobacterium | Bifidobacterium longum | B. animalis subsp. lactis NCIMB 30435 |
| Bifidobacterium | Bifidobacterium infantis | B. animalis subsp. lactis NCIMB 30436 |
| Lactobacillus | Lactobacillus acidophilus | L. acidophilus NCIMB 30442 |
| Lactobacillus | Lactobacillus plantarum | L. plantarum NCIMB 30437 |
| Lactobacillus | Lactobacillus casei | L. paracasei NCIMB 30439 |
| Lactobacillus | Lactobacillus delbrueckii subsp. bulgaricus | L. helveticus NCIMB 30440 |
Note on strain naming: Historical publications and the current CDS22-formula label use different species assignments for some of the referenced deposit codes. Probiotic.co.uk has not independently determined whether these differences reflect strain re-identification, an updated taxonomic assessment or another cause. The current CDS22-formula label information is reproduced as supplied by EOS2021 S.r.l. Readers should obtain the underlying deposit and analytical documentation from the manufacturer before drawing conclusions about identity with organisms described in historical publications.
Deposit codes can assist in identifying a named culture deposit, but a code appearing on a product label does not by itself establish that two commercial products have identical organisms, proportions, manufacturing processes or clinical equivalence.
In summary, the De Simone Formulation consists of eight bacterial strains across the Lactobacillus, Bifidobacterium, and Streptococcus genera. On the current UK CDS22-formula label these appear under NCIMB deposit codes 30435 to 30442.
CFU refers to "colony forming units", a label measure used to describe live microorganisms in a product at a given point in time. CFU numbers alone do not guarantee outcomes; strain identity and evidence alignment matter. A dose used in a clinical trial is not the same as a retail serving.
2) Timeline from published sources
The timeline below is drawn from published statements and public records, each attributed to its source. For a condition-by-condition breakdown of the published trial evidence across pouchitis, ulcerative colitis and IBS, see our evidence guide to the best probiotic for UC, IBS and pouchitis.
| Period | Stated position | Source |
|---|---|---|
| Until 2016 | The De Simone Formulation was sold under the VSL#3 brand. Older studies and guideline references to "VSL#3" therefore relate to that formulation. | ECCO, October 2023 statement [1] |
| After 2016 | The product sold as VSL#3 no longer contains the De Simone Formulation. | ECCO, October 2023 statement [1] |
| 2018 to 2021 | A Maryland jury found in 2018 that claims of equivalence between the post-2016 US VSL#3 product and the earlier formulation were false and misleading under the Lanham Act. The Fourth Circuit affirmed the verdict in February 2021, while holding part of the resulting injunction overbroad and vacating it in part. These proceedings concerned the US-marketed product and were decided under US law. They are not a ruling of any UK court. | US District Court, District of Maryland; US Court of Appeals for the Fourth Circuit [2] |
| 2024 | ESPEN published an attribution paper in Clinical Nutrition addressing how the formulation should be identified in the scientific literature. | ESPEN / Clinical Nutrition [3] |
Primary sources are listed in section 10. The practical method set out in section 8 is based on the strain list rather than on any published account.
3) The ECCO statement
ECCO (European Crohn's and Colitis Organisation) published an official statement in October 2023 stating that until 2016 DSF was sold as VSL#3, and that after 2016 the VSL#3 product no longer contains DSF [1]. ECCO also states that VSL#3 references in its 2017 guidelines should be read as relating to DSF [1]. ECCO does not reference CDS22-formula and does not endorse any retail product.
Why this matters: if you are reading a pre-2016 clinical study or a guideline reference that uses the name "VSL#3", the practical response is to compare strain lists and deposit codes on the current pack rather than to rely on any summary, including this one. Read the ECCO statement in full and draw your own conclusion.
The statement was published in ECCO News, Volume 18, Issue 3, October 2023. The copy linked above is hosted on the manufacturer's website. Readers who wish to verify it should obtain the statement from ECCO directly.
4) Where "high strength probiotics" fits (UK search intent)
In UK consumer searches, "high strength probiotics" usually means a product marketed as high-potency, often using a CFU number as a shorthand. There is no single universal definition of "high strength" across products, and CFU is only one variable.
In the UK regulatory context, probiotic products are generally regulated as food supplements rather than medicines, and health claims are restricted. No authorised UK or EU health claim currently exists for probiotic bacteria.
Neutral selection checklist (evidence-first)
- Strain identity: Which strains are included, are deposit codes given, and are they the same strains used in published human studies for the intended use?
- Dose used in evidence: Do clinical studies for a similar goal use comparable dosing and duration? A trial dose is not a serving suggestion.
- Label clarity: Is CFU stated, and is storage guidance clear?
- Safety context: People with compromised immune systems should seek clinical advice before using live microorganism products.
- Claims discipline: Treat broad "supports" claims with caution. Look for specific, sourced statements rather than generic marketing.
UK public-health guidance notes limited evidence for many probiotic health claims and advises caution for certain groups [5].
5) Identifying products on the UK market
The De Simone Formulation is the 8-strain probiotic mixture developed by Professor Claudio De Simone. Probiotic.co.uk makes no composition claim about any product other than the one it distributes, and has not independently tested any product.
- CDS22-formula. EOS2021 S.r.l. states that CDS22-formula contains the De Simone Formulation. This is a manufacturer statement, not an independent finding. The current UK label lists NCIMB 30435 to 30442.
- All other products. Refer to each manufacturer's own current published product information and pack label. Probiotic.co.uk does not characterise the composition of products it does not distribute.
Verification should be based on the strain list and deposit codes on the current pack rather than on any brand name or on any party's summary.
6) Where to obtain current specifications
Rather than characterise products we do not distribute, this table points to where current specifications can be obtained from the party responsible for each product.
| Product | Manufacturer / brand owner | Where to obtain current specifications |
|---|---|---|
| CDS22-formula | EOS2021 S.r.l. | Current UK pack label and manufacturer documentation. Lists NCIMB 30435 to 30442. |
| VSL#3 | VSL Pharmaceuticals Inc. / Actial S.r.l. | Request directly from the brand owner. |
| Vivomixx / Vivomixx Neo | Mendes SA | Request directly from the brand owner. |
| Visbiome | ExeGi Pharma | Request directly from the brand owner (US market). |
Probiotic.co.uk has not independently tested any product listed above and makes no composition claim about any product other than CDS22-formula.
7) Availability in the UK in 2026
Brand names in this category have changed more than once. The practical consequence for a UK buyer is that a brand name is not a reliable identifier. Availability should be assessed by strain list and deposit code against current manufacturer documentation.
For traceability, retain product documentation (strain list and labelling) alongside the primary sources in section 10.
8) How to verify formulation identity yourself
- Read the ECCO statement in full rather than any summary of it, including this one.
- Compare the strain list and deposit codes on the current pack, not the brand name on the front of the box.
- Request current specifications directly from the manufacturer of whichever product you are considering. Every manufacturer is an interested party, including the one we distribute.
- Check the published trial you are relying on by its PMID, and note which formulation and dose it used.
- Discuss any clinical decision with your GP or gastroenterologist. This page is not medical advice.
9) FAQs (UK)
What did ECCO state about VSL#3 and the De Simone Formulation?
ECCO published an official statement in October 2023 stating that until 2016 the De Simone Formulation was sold as VSL#3, that after 2016 the VSL#3 product no longer contains it, and that the VSL#3 references in its 2017 guidelines should be read as relating to the De Simone Formulation [1]. ECCO does not reference CDS22-formula and does not endorse any retail product. Read the statement in full and obtain current specifications from the relevant manufacturer before drawing a conclusion about any product.
Why do older studies reference VSL#3?
What was decided in the US litigation?
A Maryland jury found in 2018 that claims of equivalence between the post-2016 US VSL#3 product and the earlier formulation were false and misleading under the Lanham Act. The Fourth Circuit affirmed that verdict in February 2021, while holding part of the resulting injunction overbroad and vacating it in part [2]. Those proceedings concerned the product marketed in the United States and were decided under US law. They are not a ruling of any UK court and do not determine the composition of any product currently sold in the United Kingdom.
What is on the current CDS22-formula UK label?
The current UK label lists eight strains under NCIMB deposit codes: Streptococcus thermophilus NCIMB 30438, Bifidobacterium breve NCIMB 30441, Bifidobacterium animalis subsp. lactis NCIMB 30435 and NCIMB 30436, Lactobacillus acidophilus NCIMB 30442, Lactobacillus plantarum NCIMB 30437, Lactobacillus paracasei NCIMB 30439, and Lactobacillus helveticus NCIMB 30440. Always check the current pack, as specifications can change.
What does "high strength probiotics" mean in the UK?
In the UK, "high strength" is commonly used as a marketing label for higher potency products, often described using CFU numbers. CFU is a label measure, but a higher CFU number is not automatically "better". UK public-health guidance notes limited evidence for many probiotic health claims and advises caution for certain groups [5].
How can UK patients verify formulation identity?
Identify the strain list and deposit codes in the product documentation, confirm which formulation and dose the evidence you care about actually used, request current specifications from the manufacturer directly, and keep a record of that documentation alongside the primary sources linked below. Discuss any clinical decision with a qualified healthcare professional.
10) Source documentation
These sources are provided to support verification of the key factual distinctions used on this page. Links open external sites.
- [1] ECCO official statement (ECCO News Vol 18 Issue 3, October 2023) on the De Simone Formulation and VSL#3. Copy hosted on the manufacturer's website; obtain from ECCO directly to verify:
ECCO Official Statement, 26 October 2023 (PDF) - [2] US Court of Appeals for the Fourth Circuit, February 2021, affirming the false-advertising verdict, while vacating part of the injunction as overbroad:
https://caselaw.findlaw.com/court/us-4th-circuit/2112681.html - [3] ESPEN / Clinical Nutrition (2024), attribution in the scientific literature:
doi.org/10.1016/j.clnu.2024.05.022 - [4] Peer-reviewed overview describing the historic 8-strain mixture (PMC):
https://pmc.ncbi.nlm.nih.gov/articles/PMC7190945/ - [5] NHS guidance on probiotics (UK):
https://www.nhs.uk/tests-and-treatments/probiotics/ - [6] UK Food Standards Agency page on food supplements:
https://www.food.gov.uk/business-guidance/food-supplements
11) Editorial transparency
Author: Probiotic.co.uk Editorial Team
Market focus: United Kingdom
Published: 2026-02-23
Last updated: 2026-07-31
Editorial policy: This page summarises publicly available clinical context, attributes each statement to the published source that made it, and links to primary sources where possible. It does not characterise the position of any party that has not published one. It does not provide medical advice, diagnosis, or treatment recommendations. For clinical decisions, consult a qualified healthcare professional. This page was reviewed and amended on 31 July 2026 following an external legal review of the statements it contains.
Commercial disclosure: Probiotic.co.uk is the sole exclusive distributor of CDS22-formula for the United Kingdom and Ireland, appointed under written agreement with the manufacturer, EOS2021 S.r.l. We are not a neutral party on this subject and readers should weigh this page accordingly. Distribution documentation can be provided on request for verification purposes.
12) UK purchasing and verification
Related evidence guide
Best Probiotic for UC, IBS & Pouchitis: the evidence reviewed →The randomised trials by condition, including Gionchetti (pouchitis), Sood and Tursi (UC) and Kim (IBS), plus the AGA pouchitis guideline.