VSL3 Alternative UK: The Original De Simone Formulation is Now CDS22-formula
VSL3 Alternative UK:
The Original Formula Has a New Name
The De Simone Formulation that was once sold as VSL#3 probiotic, and then as Vivomixx, is now available in the UK as CDS22-formula. Same 8 strains. Same 450 billion CFU. New name.
| Question | Verified Answer | Primary Source |
|---|---|---|
| Does current VSL#3 contain the original De Simone Formulation? | No. Post-2016 VSL#3 does not contain the De Simone Formulation. | ECCO statement, Oct 2023 |
| Which product in the UK contains the original De Simone Formulation today? | CDS22-formula, available from Probiotic.co.uk. | CDS22 manufacturer documentation |
| Which probiotic is cited in AGA pouchitis guidelines? | The De Simone Formulation specifically, with 87% lower relapse risk over 12 months across three RCTs. | AGA Guideline, Gastroenterology 2024 |
| Did a court find VSL#3 is not the original formulation? | Yes. A US federal court ruled the post-split VSL#3 is not the original De Simone Formulation. | US 4th Circuit Court, 2021 |
| Is Vivomixx Neo the same as the original De Simone Formulation? | No. Vivomixx Neo uses a different formulation introduced in 2024. | Probiotic.co.uk comparison guide |
What Happened to the Original VSL3 Probiotic Formula?
VSL#3 probiotic was originally formulated around a specific 8-strain blend developed by Professor Claudio De Simone, an Italian microbiologist and clinician. This combination, now formally called the De Simone Formulation (DSF), was the subject of clinical trials published in Gastroenterology and Gut from 2000 onwards, and has accumulated over 80 clinical trials and 200 peer-reviewed publications.
In 2016, a commercial separation occurred between Professor De Simone and the VSL#3 brand owner (Actial Srl). The outcome:
- The VSL#3 brand name remained with Actial Srl. The product was subsequently reformulated using different strains from a different cell bank source.
- The original De Simone Formulation remained with its inventor and continued under new brand names in different markets.
A US federal appeals court ruled in 2021 that the product sold as VSL#3 after the split was not the same formulation as the one used in the pre-2016 clinical research.[1] ECCO issued an official clarification in October 2023 confirming the same position for clinicians and patients across Europe.[2]
The practical result: the brand name "VSL#3" and the original De Simone Formulation now refer to two different products.
Full Timeline: VSL#3 to Vivomixx to CDS22
VSL#3 Era: Landmark Clinical Evidence Built
The De Simone Formulation is sold as VSL#3 probiotic. Clinical trials by Gionchetti et al. (2000, 2003) in Gastroenterology and Mimura et al. (2004) in Gut establish the evidence base for pouchitis prevention and remission maintenance. These are the trials referenced today in ECCO IBD guidelines and AGA pouchitis guidelines.
Commercial Split: Brand and Formulation Separate
Professor De Simone separates from Actial Srl. The original 8-strain formula stays with its inventor, with the original DSM strain codes and master cell bank. The VSL#3 brand continues with a reformulated product. From this date, the VSL#3 brand and the De Simone Formulation are distinct entities.[2]
Vivomixx 450 (UK/EU) and Visbiome (US)
The original De Simone Formulation is relaunched as Vivomixx 450 in the UK and EU (distributed by Mendes SA) and as Visbiome in the United States. Both contain the identical 8 strains at 450 billion CFU. UK consumers accessing the clinically-studied formulation used Vivomixx 450 sachets during this period.
Vivomixx Neo Introduced: A Different Formulation
Mendes SA launches Vivomixx Neo under the Vivomixx brand name using a different formulation. Vivomixx Neo does not contain the original De Simone Formulation strains. The original Vivomixx 450 is discontinued in 2025. This creates significant confusion for UK consumers who assume brand continuity equals formulation continuity.
CDS22-Formula: Direct Formulation Continuation
CDS22-formula is launched as the direct replacement for original Vivomixx 450, containing the exact same 8 strains at the same DSM codes, from the same original master cell bank, at 450 billion CFU per sachet. It is currently the only product in the UK carrying the original De Simone Formulation.[3]
What ECCO and AGA Guidelines Say
Two major clinical bodies have issued relevant guidance that directly addresses the De Simone Formulation and its relationship to VSL#3. Both are important context for UK patients and clinicians.
ECCO (European Crohn's and Colitis Organisation)
ECCO has confirmed: (1) Until 2016, the De Simone Formulation was sold as VSL#3. (2) After 2016, the product sold as VSL#3 no longer contains the De Simone Formulation. (3) VSL#3 references in ECCO's 2017 IBD guidelines exclusively endorse the De Simone Formulation, because post-2016 VSL#3 does not contain it. Source: ecco-ibd.eu, October 2023[2]
In practical terms: if a clinician or patient is reading a guideline or published study that references VSL#3 probiotic in the context of IBD, pouchitis, or IBS, that reference relates to the De Simone Formulation, not to the current VSL#3 product.
AGA (American Gastroenterological Association)
The AGA guideline (Barnes EL et al., Gastroenterology 2024;166(1):59-85) specifically identifies the De Simone Formulation as the multi-strain probiotic used in the clinical trials reviewed for its recommendation on secondary prevention of recurrent pouchitis. Across three RCTs, the De Simone Formulation was associated with an 87% lower risk of relapse over 12 months. The guideline notes: "The body of evidence favoring the use of probiotics for preventing recurrence of pouchitis is limited to the De Simone formulation." Source: gastrojournal.org[4]
Note: both guidelines reference the De Simone Formulation directly, not a brand name. Patients and clinicians using these guidelines to inform product choice should verify that the product used contains the original De Simone Formulation strains and cell bank source, not simply a product that shares a historical brand name.
Strain-Level Comparison: CDS22 vs Current VSL#3 vs Vivomixx Neo
ECCO's recommended method for verifying formulation identity is strain-level comparison, not brand name. The table below compares the eight strains of the original De Simone Formulation (as found in CDS22-formula) with the current VSL#3 product and Vivomixx Neo.
Note on the current VSL#3 product: VSL#3 uses some species names that overlap with the De Simone Formulation, but the strain codes differ from the original DSM codes, and the bacterial sources come from a different cell bank. Formulation identity in clinical research is determined by strain code and cell bank source, not by species name alone.
| Original DSF Strain | CDS22-formula (original DSM code) | Current VSL#3 | Vivomixx Neo |
|---|---|---|---|
| Lactobacillus acidophilus | DSM 24735 | Different strain code (BA05) | Different formulation |
| Lactobacillus plantarum | DSM 24730 | Different strain code (BP06) | Different formulation |
| Lactobacillus paracasei | DSM 24733 | Different strain code (BP07) | Different formulation |
| L. delbrueckii subsp. bulgaricus | DSM 24734 | Not part of current VSL#3 DSF strain set | Different formulation |
| Bifidobacterium longum | DSM 24736 | Not part of current VSL#3 DSF strain set | Different formulation |
| Bifidobacterium infantis | DSM 24737 | Not part of current VSL#3 DSF strain set | Different formulation |
| Bifidobacterium breve | DSM 24732 | Different strain code (BB02) | Different formulation |
| Streptococcus thermophilus | DSM 24731 | Different strain code (BT01) | Different formulation |
| Cell bank source | Original DSF master cell bank | Different cell bank source | Different formulation |
| Matches original De Simone Formulation? | Yes | No (post-2016 reformulation) | No (different formulation) |
| ECCO and AGA guideline evidence applies? | Yes | No | No |
CDS22-formula DSM strain codes from public manufacturer documentation. Current VSL#3 strain codes from publicly available label information. Vivomixx Neo described as a different formulation based on manufacturer materials. Always verify against current manufacturer documentation in your market before making clinical decisions.
How to Verify Formulation Identity Yourself
Rather than relying on brand names or marketing claims, formulation identity can be verified directly using publicly available sources. This is the approach ECCO recommends.
Four-step verification process
- Check the ECCO statement. Read the October 2023 ECCO official statement at ecco-ibd.eu. It confirms directly that post-2016 VSL#3 does not contain the De Simone Formulation.
- Compare strain codes, not species names. The De Simone Formulation strains carry specific DSM codes (DSM 24730 through DSM 24737). Request or locate the current product label and check whether the listed strain codes match these original DSM codes.
- Check the cell bank source. The original De Simone Formulation was produced from a specific original master cell bank. Products using the same species names but sourced from different cell banks are not equivalent for clinical purposes.
- Cross-reference manufacturer documentation. For CDS22-formula, documentation is available at cds22.com and from Probiotic.co.uk as the authorised UK distributor. Retain any documentation alongside primary sources for traceability.
Which Products Contain the Original De Simone Formulation in the UK?
| Product | Contains Original DSF? | Status in 2026 | UK Availability |
|---|---|---|---|
| CDS22-formula | Yes — original strains and cell bank | Current | Available from Probiotic.co.uk |
| Visbiome (US) | Yes | Current | US market only |
| Original Vivomixx 450 | Yes | Discontinued 2025 | No longer available |
| VSL#3 (current) | No — reformulated post-2016 | Current | Available, different formulation |
| Vivomixx Neo | No — different formulation | Current | Available, different formulation |
Based on the ECCO October 2023 statement, the AGA 2024 guideline, US federal court findings, and publicly available manufacturer documentation: CDS22-formula is the product in the UK whose strain codes and cell bank source most closely match the original De Simone Formulation used in the clinical trials that underpin current IBD and pouchitis guideline recommendations. Consumers and clinicians should verify this independently using the four-step process above.
CDS22-formula: Available from the UK Authorised Distributor
450 billion CFU per sachet. Original 8 strains. Cold-chain protected. Tracked next-day delivery across the UK from our Lancashire facility.
Shop CDS22-formulaVSL3 Alternative UK: Common Questions Answered
For consumers specifically seeking the original De Simone Formulation that was in VSL#3 before 2016, CDS22-formula is the closest match available in the UK. It uses the same 8 strains at the same DSM codes from the same original master cell bank. The current VSL#3 uses different strain codes and a different cell bank source. Source: ECCO official statement.
No. After the 2016 commercial separation, the product sold as VSL#3 no longer contains the original De Simone Formulation. ECCO confirmed this in October 2023. Three of the eight original DSF strains (DSM 24734, DSM 24736, DSM 24737) are not part of the current VSL#3 strain set, and the remaining strains carry different strain codes from different bacterial sources.
Both guidelines reference the De Simone Formulation specifically. The AGA 2024 pouchitis guideline (Barnes et al., Gastroenterology 166(1):59-85) identifies the De Simone Formulation as the probiotic used in the trials showing 87% lower relapse risk over 12 months. ECCO's 2017 IBD guideline references, clarified in 2023, also relate to the De Simone Formulation. CDS22-formula contains the De Simone Formulation in the UK today.
CDS22-formula contains eight strains at their original DSM codes (DSM 24730 to DSM 24737) from the original master cell bank. The current VSL#3 uses different strain codes and a different cell bank. Three strains in the original De Simone Formulation (DSM 24734, DSM 24736, DSM 24737) are not part of the current VSL#3 strain set. Strain code and cell bank source determine clinical identity, not species name alone.
No. Vivomixx Neo, introduced by Mendes SA in 2024, uses a different formulation. Original Vivomixx 450 (which contained the De Simone Formulation) was discontinued in 2025. CDS22-formula is the direct formulation continuation of original Vivomixx 450 with the same strains, codes, and potency.
Use the four-step process described in this guide: check the ECCO statement, compare DSM strain codes (DSM 24730 to 24737) against the product label, check the cell bank source, and cross-reference manufacturer documentation. Brand name alone is not a reliable indicator after the 2016 commercial split.
CDS22-formula is available from Probiotic.co.uk, the authorised UK distributor. Orders are dispatched from a temperature-controlled facility in Lancashire with cold-chain packaging and tracked next-day delivery across the UK including Northern Ireland.
Further Reading on the De Simone Formulation
Sources and References
- [1] US Fourth Circuit Court: De Simone LLC v. VSL (2021) — caselaw.findlaw.com
- [2] ECCO Official Statement, October 2023 — ecco-ibd.eu
- [3] CDS22-formula manufacturer: cds22.com
- [4] Barnes EL et al. AGA Clinical Practice Guideline on the Management of Pouchitis and Inflammatory Pouch Disorders. Gastroenterology. 2024 Jan;166(1):59-85 — gastrojournal.org
- [5] US Fourth Circuit Court (2022): Claudio De Simone v. VSL Pharmaceuticals — law.justia.com
- [6] PMC: Peer-reviewed overview of historic 8-strain VSL#3 mixture — pmc.ncbi.nlm.nih.gov
- [7] NHS guidance on probiotics — nhs.uk
- [8] CDS22-formula clinical studies bibliography — probiotic.co.uk