I'll give you a freedom-to-operate read on a naked anti-CLDN18.2 mAb. Let me start by orienting myself in the corpus and pulling the relevant CLDN18.2 families.
{
"n_families": 14,
"targets": {
"CLDN18.2": {
"modalities": [
"Antibody-drug conjugate",
"Naked monoclonal antibody"
],
"n_families": 6
},
"HER2": {
"modalities": [
"Antibody-drug conjugate",
"Naked monoclonal antibody"
],
"n_families": 4
},
"DLL3": {
"modalities": [
"Antibody-drug conjugate",
"T-cell engager (bispecific)"
],
"n_families": 4
}
},
"assignees": [
"AbbVie / Stemcentrx",
"Amgen",
"Astellas Pharma",
"Boehringer Ingelheim",
"Byondis",
"Daiichi Sankyo",
"Ganymed Pharmaceuticals",
"Ganymed Pharmaceuticals / Astellas",
"Genentech",
"Harbour BioMed",
"ImmunoGen",
"Keymed Biosciences",
"LaNova Medicines",
"Sotio Biotech"
],
"jurisdictions": [
"CN",
"US",
"WO"
]
}{
"count": 6,
"families": [
{
"publication_number": "US9051370B2",
"jurisdiction": "US",
"assignee": "Ganymed Pharmaceuticals / Astellas",
"title": "Antibodies binding to CLDN18.2 and uses thereof",
"target": "CLDN18.2",
"modality": "Naked monoclonal antibody",
"priority_date": "2008-01-03",
"expiry": "2029-01-03",
"legal_status": "GRANTED",
"claim_types": [
"composition",
"method"
],
"keywords": [
"CLDN18.2",
"claudin",
"zolbetuximab",
"naked antibody",
"gastric",
"composition of matter",
"extracellular loop"
]
},
{
"publication_number": "WO2016166122A1",
"jurisdiction": "WO",
"assignee": "Astellas Pharma",
"title": "Combination therapy of a CLDN18.2 antibody with chemotherapy",
"target": "CLDN18.2",
"modality": "Naked monoclonal antibody",
"priority_date": "2015-04-13",
"expiry": "2036-04-13",
"legal_status": "PENDING",
"claim_types": [
"method"
],
"keywords": [
"CLDN18.2",
"combination",
"chemotherapy",
"gastric",
"GEJ",
"method of treatment",
"first line"
]
},
{
"publication_number": "CN103509118A",
"jurisdiction": "CN",
"assignee": "Ganymed Pharmaceuticals",
"title": "Antibodies for the diagnosis and treatment of claudin-18.2 expressing tumours",
"target": "CLDN18.2",
"modality": "Naked monoclonal antibody",
"priority_date": "2009-11-24",
"expiry": "2018-11-24",
"legal_status": "EXPIRED",
"claim_types": [
"composition"
],
"keywords": [
"CLDN18.2",
"diagnostic",
"imaging",
"expired",
"early filing"
]
},
{
"publication_number": "WO2019173420A1",
"jurisdiction": "WO",
"assignee": "LaNova Medicines",
"title": "Anti-CLDN18.2 antibody-drug conjugates with a cleavable linker",
"target": "CLDN18.2",
"modality": "Antibody-drug conjugate",
"priority_date": "2018-03-08",
"expiry": "2039-03-08",
"legal_status": "GRANTED",
"claim_types": [
"composition",
"method"
],
"keywords": [
"CLDN18.2",
"ADC",
"MMAE",
"auristatin",
"cleavable linker",
"DAR",
"composition of matter",
"payload genus"
]
},
{
"publication_number": "CN114106192A",
"jurisdiction": "CN",
"assignee": "Keymed Biosciences",
"title": "Anti-claudin18.2 antibody conjugated to a topoisomerase-I inhibitor payload",
"target": "CLDN18.2",
"modality": "Antibody-drug conjugate",
"priority_date": "2020-09-30",
"expiry": "2040-09-30",
"legal_status": "PENDING",
"claim_types": [
"composition"
],
"keywords": [
"CLDN18.2",
"ADC",
"topoisomerase",
"exatecan",
"DXd",
"cleavable linker",
"pending",
"China"
]
},
{
"publication_number": "US11078291B2",
"jurisdiction": "US",
"assignee": "Sotio Biotech",
"title": "Maytansinoid antibody-drug conjugates targeting CLDN18.2",
"target": "CLDN18.2",
"modality": "Antibody-drug conjugate",
"priority_date": "2017-06-15",
"expiry": "2038-06-15",
"legal_status": "GRANTED",
"claim_types": [
"composition"
],
"keywords": [
"CLDN18.2",
"ADC",
"maytansinoid",
"DM1",
"DM4",
"non-cleavable linker",
"composition of matter"
]
}
]
}The naked-mAb families are the ones that matter for FTO (the ADC families claim conjugates, generally not infringed by a naked antibody, but I'll verify the key one's claim scope). Let me read the actual claims of the three naked-mAb families plus the Sotio ADC to confirm the conjugate limitation.
{
"publication_number": "US9051370B2",
"title": "Antibodies binding to CLDN18.2 and uses thereof",
"legal_status": "GRANTED",
"independent_claims": [
{
"claim_no": 1,
"claim_type": "composition",
"text": "A monoclonal antibody that binds to the extracellular loop of human Claudin-18 splice variant 2 (CLDN18.2) but does not bind CLDN18.1, covering the antibody and antigen-binding fragments thereof."
},
{
"claim_no": 14,
"claim_type": "method",
"text": "A method of treating a CLDN18.2-positive cancer comprising administering the antibody of claim 1."
}
]
}{
"publication_number": "WO2016166122A1",
"title": "Combination therapy of a CLDN18.2 antibody with chemotherapy",
"legal_status": "PENDING",
"independent_claims": [
{
"claim_no": 1,
"claim_type": "method",
"text": "A method of treating gastric or gastro-oesophageal junction adenocarcinoma comprising administering an anti-CLDN18.2 antibody in combination with a fluoropyrimidine- and platinum-containing chemotherapy regimen."
}
]
}{
"publication_number": "CN103509118A",
"title": "Antibodies for the diagnosis and treatment of claudin-18.2 expressing tumours",
"legal_status": "EXPIRED",
"independent_claims": [
{
"claim_no": 1,
"claim_type": "composition",
"text": "An antibody binding CLDN18.2 conjugated to a detectable label for diagnostic imaging of claudin-18.2-expressing tumours."
}
]
}{
"publication_number": "US11078291B2",
"title": "Maytansinoid antibody-drug conjugates targeting CLDN18.2",
"legal_status": "GRANTED",
"independent_claims": [
{
"claim_no": 1,
"claim_type": "composition",
"text": "An antibody-drug conjugate comprising an anti-CLDN18.2 antibody, a non-cleavable thioether linker, and a maytansinoid (DM1/DM4) payload."
}
]
}I have what I need. Here's the FTO read.
1. US9051370B2 (Ganymed/Astellas) — the genus composition-of-matter claim. This is your primary blocker.
- Claim 1 covers "a monoclonal antibody that binds the extracellular loop of human CLDN18.2 but does not bind CLDN18.1" — and antigen-binding fragments.
- This is a broad genus claim defined functionally by epitope/binding specificity, not limited to zolbetuximab's sequence. Your described product — a naked mAb binding the CLDN18.2 extracellular loop, CLDN18.1-sparing — reads squarely inside this claim. The fact that it's the zolbetuximab class makes the overlap essentially certain.
- Claim 14 separately covers the method of treating CLDN18.2-positive cancer with that antibody.
- GRANTED, expires 2029-01-03. This is a hard block on both the composition and the use.
2. WO2016166122A1 (Astellas) — combination/method-of-use blocker for your exact regimen.
- Claim 1: anti-CLDN18.2 antibody + fluoropyrimidine + platinum chemo in gastric/GEJ adenocarcinoma.
- This maps directly onto the registered 1L use (zolbetuximab + mFOLFOX6/CAPOX). So even after the genus composition claim expires, the first-line combination method is separately claimed.
- PENDING, expiry 2036-04-13 if granted. Watch prosecution — scope may narrow, and it's a method claim (only blocks the labeled combo use, not the molecule).
The ADCs are not a problem. The real questions are the two Astellas/Ganymed families:
US9051370B2 (the genus claim) is the gating issue, and it's hard to design around because the claim is functional (epitope + CLDN18.1 sparing), not sequence-based. A differentiated CDR sequence does not get you out — to clear by design you'd have to bind a different epitope or lose CLDN18.1 selectivity, which defeats the "zolbetuximab-class" product rationale. Practical options:
- Wait it out / time the launch. It expires Jan 3, 2029 (check for any PTE/term adjustment and ex-US equivalents, which aren't in this corpus). A US launch after expiry is clean on the composition claim.
- License from Astellas if you want to enter before 2029.
- Validity challenge — a functional genus claim from a 2008 priority date may be vulnerable on written-description/enablement grounds (does the spec enable the full functional genus or just the disclosed antibodies?). Worth a patentability/validity opinion before relying on it.
WO2016166122A1 (1L combo method) — this is a method-of-use claim. Even if US9051370B2 expires in 2029, this could block the first-line fluoropyrimidine+platinum combination through ~2036 if granted. Mitigations:
- Monitor its prosecution and final granted scope; method claims often narrow.
- Consider a non-infringing regimen / label (different chemo backbone or monotherapy/other-line positioning) — though that compromises the 1L combo strategy that's the point of the program.
- Re-assess validity once granted.
Two caveats: this corpus is US/WO/CN only, so confirm ex-US (EP/JP) equivalents and any patent term extension on US9051370B2, both of which could shift the 2029 date. If you tell me which markets you're prioritizing, I can dig further into jurisdiction-specific status.
I have what I need. Here's the FTO read.
1. US9051370B2 (Ganymed/Astellas) — the genus composition-of-matter claim. This is your primary blocker.
- Claim 1 covers "a monoclonal antibody that binds the extracellular loop of human CLDN18.2 but does not bind CLDN18.1" — and antigen-binding fragments.
- This is a broad genus claim defined functionally by epitope/binding specificity, not limited to zolbetuximab's sequence. Your described product — a naked mAb binding the CLDN18.2 extracellular loop, CLDN18.1-sparing — reads squarely inside this claim. The fact that it's the zolbetuximab class makes the overlap essentially certain.
- Claim 14 separately covers the method of treating CLDN18.2-positive cancer with that antibody.
- GRANTED, expires 2029-01-03. This is a hard block on both the composition and the use.
2. WO2016166122A1 (Astellas) — combination/method-of-use blocker for your exact regimen.
- Claim 1: anti-CLDN18.2 antibody + fluoropyrimidine + platinum chemo in gastric/GEJ adenocarcinoma.
- This maps directly onto the registered 1L use (zolbetuximab + mFOLFOX6/CAPOX). So even after the genus composition claim expires, the first-line combination method is separately claimed.
- PENDING, expiry 2036-04-13 if granted. Watch prosecution — scope may narrow, and it's a method claim (only blocks the labeled combo use, not the molecule).
The ADCs are not a problem. The real questions are the two Astellas/Ganymed families:
US9051370B2 (the genus claim) is the gating issue, and it's hard to design around because the claim is functional (epitope + CLDN18.1 sparing), not sequence-based. A differentiated CDR sequence does not get you out — to clear by design you'd have to bind a different epitope or lose CLDN18.1 selectivity, which defeats the "zolbetuximab-class" product rationale. Practical options:
- Wait it out / time the launch. It expires Jan 3, 2029 (check for any PTE/term adjustment and ex-US equivalents, which aren't in this corpus). A US launch after expiry is clean on the composition claim.
- License from Astellas if you want to enter before 2029.
- Validity challenge — a functional genus claim from a 2008 priority date may be vulnerable on written-description/enablement grounds (does the spec enable the full functional genus or just the disclosed antibodies?). Worth a patentability/validity opinion before relying on it.
WO2016166122A1 (1L combo method) — this is a method-of-use claim. Even if US9051370B2 expires in 2029, this could block the first-line fluoropyrimidine+platinum combination through ~2036 if granted. Mitigations:
- Monitor its prosecution and final granted scope; method claims often narrow.
- Consider a non-infringing regimen / label (different chemo backbone or monotherapy/other-line positioning) — though that compromises the 1L combo strategy that's the point of the program.
- Re-assess validity once granted.
Two caveats: this corpus is US/WO/CN only, so confirm ex-US (EP/JP) equivalents and any patent term extension on US9051370B2, both of which could shift the 2029 date. If you tell me which markets you're prioritizing, I can dig further into jurisdiction-specific status.
Heuristic reference over the curated corpus for target=CLDN18.2, modality=Naked monoclonal antibody. Families in scope: 6 ({'GRANTED': 3, 'PENDING': 2, 'EXPIRED': 1}). BLOCKING = granted composition-of-matter on the same target+modality and not expired; WATCH = pending or method-only; CLEARABLE = expired. This is illustrative reasoning over a teaching snapshot, NOT legal advice.
| Publication # | Assignee | Legal status | Expiry | Claim type(s) | FTO relevance |
|---|---|---|---|---|---|
| US9051370B2 | Ganymed Pharmaceuticals / Astellas | GRANTED | 2029-01-03 | composition, method | BLOCKING (granted composition-of-matter) |
| WO2016166122A1 | Astellas Pharma | PENDING | 2036-04-13 | method | WATCH (pending — claims not yet fixed) |
| CN103509118A | Ganymed Pharmaceuticals | EXPIRED | 2018-11-24 | composition | CLEARABLE (expired) |
| WO2019173420A1 | LaNova Medicines | GRANTED | 2039-03-08 | composition, method | BLOCKING (granted composition-of-matter) |
| CN114106192A | Keymed Biosciences | PENDING | 2040-09-30 | composition | WATCH (pending — claims not yet fixed) |
| US11078291B2 | Sotio Biotech | GRANTED | 2038-06-15 | composition | BLOCKING (granted composition-of-matter) |
| OVERALL FTO VERDICT (heuristic) | BLOCKED — 3 granted composition-of-matter family(ies) read on the proposed product; need a licence or a design-around. |