Investigational Drug Information for Tipifarnib

What is the development status for investigational drug Tipifarnib?

Tipifarnib is an investigational drug.

There have been 86 clinical trials for Tipifarnib. The most recent clinical trial was a Phase 3 trial, which was initiated on December 6^th 2024.

The most common disease conditions in clinical trials are Leukemia, Leukemia, Myeloid, and Leukemia, Myeloid, Acute. The leading clinical trial sponsors are National Cancer Institute (NCI), Kura Oncology, Inc., and Johnson & Johnson Pharmaceutical Research & Development, L.L.C.

There are zero US patents protecting this investigational drug and zero international patents.

Summary for Tipifarnib

US Patents	1,797
International Patents	8,084
US Patent Applications	6,974
WIPO Patent Applications	0
Japanese Patent Applications	708
Clinical Trial Progress	Phase 3 (2024-12-06)
Vendors	55

Recent Clinical Trials for Tipifarnib

Title	Sponsor	Phase
Tipifarnib and Naxitamab for Relapsed/Refractory Neuroblastoma	Giselle Sholler	PHASE2
Tipifarnib and Osimertinib in EGFR-mutated Non-Small Cell Lung Cancer	Kura Oncology, Inc.	Phase 1
Clinical Study of Azacitidine Combined With Ruxolitinib in the Treatment of Higher-risk MDS/MPN	Jiangbin Hospital Affiliated to Jiangsu University	Phase 2

See all Tipifarnib clinical trials

Clinical Trial Summary for Tipifarnib

Top disease conditions for Tipifarnib

Top clinical trial sponsors for Tipifarnib

See all Tipifarnib clinical trials

US Patents for Tipifarnib

Drugname	Patent Number	Patent Title	Patent Assignee	Estimated Expiration
Tipifarnib		Heat shock protein 70 (hsp-70) receptor ligands	Duke University (Durham, NC)
Tipifarnib		Compounds and their methods of use	Agios Pharmaceuticals, Inc. (Cambridge, MA)
Tipifarnib

International Patents for Tipifarnib

Drugname	Country	Document Number	Estimated Expiration	Related US Patent
Tipifarnib	World Intellectual Property Organization (WIPO)	WO2015148714	2034-03-25
Tipifarnib	Australia	AU2015231053	2034-03-21
Tipifarnib	Brazil	BR112016021620	2034-03-21

Tipifarnib Development Update, Patent Position, FDA Status, and Market Projection

Last updated: September 4, 2026

Tipifarnib is an oral farnesyltransferase inhibitor developed primarily for HRAS-mutant head and neck squamous cell carcinoma (HNSCC). Its clinical activity is strongest in biomarker-selected patients, but the program has not reached U.S. approval. The FDA issued a Complete Response Letter for the HNSCC application in November 2021, and no commercial launch or Orange Book listing followed. Tipifarnib’s near-term market value therefore depends on whether the sponsor can generate confirmatory evidence in HRAS-mutant disease or identify a new development partner.

What is tipifarnib and how does it work?

Tipifarnib, also known as R115777, is a selective inhibitor of farnesyltransferase. The enzyme adds a farnesyl lipid group to proteins required for intracellular signaling. Tipifarnib was designed to disrupt signaling from several farnesylated proteins, including RAS-family proteins.

HRAS is particularly relevant because HRAS remains dependent on farnesylation for membrane localization. This creates a biological rationale for tipifarnib in tumors with activating HRAS mutations, while KRAS and NRAS can often escape farnesyltransferase inhibition through alternative geranylgeranylation pathways.

Tipifarnib is administered orally. Its principal development focus has been recurrent or metastatic HNSCC with HRAS mutations, a small molecularly defined population representing roughly 3% to 8% of HNSCC cases, depending on the study population and testing method (Ho et al., 2021; Kura Oncology, 2021).

What is the current development status of tipifarnib?

Tipifarnib has no FDA-approved indication as of the latest publicly established regulatory record. The major development milestones are as follows:

Date	Development event	Commercial significance
1990s-2000s	Broad oncology development by Johnson & Johnson and affiliated entities	Multiple studies produced mixed results in unselected cancers
2014	Kura Oncology obtained rights to develop tipifarnib	Program shifted toward biomarker-selected disease
2018-2019	Positive activity reported in HRAS-mutant HNSCC	Supported Breakthrough Therapy designation
2019	FDA granted Breakthrough Therapy designation for relapsed or metastatic HRAS-mutant HNSCC after platinum therapy	Accelerated regulatory interaction, but not approval
2021	FDA accepted the NDA for review	Program reached formal U.S. regulatory review
November 2021	FDA issued a Complete Response Letter	No approval; additional evidence was required
2022-2024	No U.S. launch and no publicly established approval pathway	Asset remained commercially unvalidated

Kura reported that the FDA’s Complete Response Letter did not identify a new safety signal. The central issue was the need for additional clinical evidence supporting efficacy and the proposed benefit-risk profile in HRAS-mutant HNSCC (Kura Oncology, 2021).

No subsequent FDA approval, confirmatory filing, or publicly disclosed relaunch has established tipifarnib as an active late-stage commercial program. The development program should therefore be classified as regulatory risk with uncertain continuation rather than as a near-term launch asset.

What clinical evidence supports tipifarnib in HRAS-mutant HNSCC?

The strongest evidence came from the AIM-HN study, a multicenter Phase 2 trial in patients with recurrent or metastatic HNSCC carrying HRAS mutations. Patients had limited treatment options and had generally received prior platinum-based therapy.

Reported results included:

Metric	Reported result
Overall response rate in the primary efficacy population	Approximately 55%
Median duration of response	Approximately 20 months
Patient population	Recurrent or metastatic HRAS-mutant HNSCC
Treatment setting	Heavily pretreated disease
Biomarker	Activating HRAS mutation

The response rate and durability were materially higher than historical expectations for many later-line HNSCC treatments. The evidence was generated in a small, non-randomized population, however. That limited the ability to separate treatment effect from patient-selection effects and created a regulatory burden for a full approval.

The program’s central technical risk is the size and heterogeneity of the HRAS-mutant population. HRAS mutations occur at low frequency, mutation location may affect sensitivity, and tumor response may vary by prior therapy, mutation allele, and disease site. A commercially viable program would require reliable mutation testing, rapid identification of eligible patients, and additional evidence in a population that is difficult to recruit.

What is the FDA regulatory status of tipifarnib?

Tipifarnib does not have FDA approval for HNSCC, AML, myelodysplastic syndromes, or another cancer indication.

The relevant regulatory status is:

Regulatory item	Status
FDA approval	None established
Breakthrough Therapy designation	Granted for HRAS-mutant HNSCC
NDA	Submitted and reviewed
FDA action	Complete Response Letter in November 2021
Current U.S. commercial status	Not marketed as an approved oncology drug
Companion diagnostic approval	No approved tipifarnib companion diagnostic established
Orange Book listing	No listed approved tipifarnib product identified

Breakthrough Therapy designation does not guarantee approval. It accelerates development interaction and permits intensive FDA guidance, but the sponsor must still demonstrate substantial evidence of effectiveness.

What patents protect tipifarnib?

Tipifarnib’s composition-of-matter protection is old relative to most late-stage oncology assets. The original patent estate was developed before Kura Oncology acquired the program and has largely faced the normal erosion associated with an asset discovered in the 1990s.

Publicly reported sources identify early U.S. patent protection for the quinolinone-based farnesyltransferase inhibitor series, including patents associated with R115777 and Janssen-affiliated entities. The precise enforceability of individual patents depends on terminal disclaimers, patent-term adjustment, prosecution history, and jurisdiction-specific maintenance. No current Orange Book patent listing provides an approved-product framework because tipifarnib has not received U.S. approval.

Protection category	Practical status
Composition of matter	Original protection is historic and likely expired or near expiration in major markets
Pharmaceutical compositions	May include formulation or dosage-form claims, but current enforceability is not established by an approved-product listing
Methods of treatment	Potentially relevant to HRAS-mutant cancer, but claim scope depends on issued claims and prosecution history
Biomarker-selected use	May provide later-filed protection if valid claims cover HRAS mutation testing and treatment
Manufacturing methods	Could create process barriers, but no commercially decisive current process estate is publicly established
U.S. Orange Book linkage	Not applicable without an approved reference product

The absence of an Orange Book listing does not mean that every patent claim has expired. It means that tipifarnib does not currently have the standard U.S. approved-drug patent-and-exclusivity framework used for an marketed small-molecule reference product.

When does tipifarnib lose exclusivity?

Tipifarnib has no active U.S. regulatory exclusivity period because it has not been approved.

The principal exclusivity dates are therefore:

Exclusivity type	Status
New chemical entity exclusivity	Not triggered because no FDA approval exists
Orphan-drug exclusivity	No established FDA orphan approval for tipifarnib
Pediatric exclusivity	None established
GAIN Act exclusivity	None established
Patent exclusivity	Original composition protection is historical; current enforceable term must be assessed patent by patent
Market exclusivity	No current U.S. market exclusivity

If tipifarnib were refiled and approved for a new molecularly defined indication, the sponsor could seek orphan designation and related exclusivity if the patient population and statutory criteria were satisfied. That protection would attach only after a qualifying approval and would not revive expired composition patents.

What formulation patents and manufacturing barriers affect tipifarnib?

Tipifarnib’s principal commercial form is an oral solid dosage product. Formulation value would depend on claims covering salt form, polymorph, dissolution profile, stability, modified release, or a specific dosing regimen.

No formulation patent has been publicly established as the decisive barrier to generic entry. The more important commercial constraint is likely clinical and regulatory rather than manufacturing complexity. Tipifarnib is a small molecule with no biologic manufacturing hurdle, no cell-line requirement, and no biosimilar pathway.

Potential technical barriers include:

• Reproducible control of solid-state form.
• Tablet dissolution and bioavailability.
• Stability under commercial storage conditions.
• Manufacturing control for active pharmaceutical ingredient impurities.
• Clinical bridging for a new formulation or dosing schedule.
• Validation of a companion diagnostic for HRAS mutations.

These issues can delay a generic or reformulated product but normally do not create the same barrier as a complex biologic, long-acting injectable, or highly specialized delivery system.

What patent litigation and Paragraph IV challenges affect tipifarnib?

No significant public U.S. patent litigation or Paragraph IV dispute has established a current generic-entry timeline for tipifarnib.

That result follows from the drug’s regulatory status. A Paragraph IV challenge ordinarily targets patents listed for an FDA-approved reference product. Because tipifarnib has not produced an approved U.S. reference product, there is no conventional Orange Book litigation pathway for a generic applicant to attack.

Potential future litigation could arise if:

1. Tipifarnib receives approval.
2. The sponsor obtains listing-eligible formulation or method-of-use patents.
3. A generic applicant files an Abbreviated New Drug Application.
4. The sponsor sues within the statutory 45-day period following a Paragraph IV notice.

Without an approved reference product, projected litigation timing remains speculative and should not be treated as an established launch event.

How strong is the tipifarnib patent estate?

The patent estate is weaker than the clinical differentiation.

Strengths

• A clear mechanism linked to HRAS biology.
• Potential use patents tied to a defined mutation-positive population.
• Possibility of diagnostic-treatment claims if properly drafted and enforceable.
• Historical know-how in formulation, dosing, and patient selection.

Weaknesses

• Old discovery date and likely erosion of original composition protection.
• No Orange Book-listed patents supporting an approved product.
• Small commercial population limits the economic value of litigation.
• Method-of-use claims may face validity and written-description challenges.
• Biomarker claims can be difficult to enforce against indirect treatment decisions.
• No established regulatory exclusivity.

The estate would become materially stronger if a new approval generated later-filed, unexpired patents covering a specific HRAS-mutant indication, dosing schedule, or combination regimen. Those rights would still need to survive obviousness, enablement, written-description, and patentable-subject-matter challenges.

Which companies are challenging tipifarnib?

No major generic company has publicly established a U.S. Paragraph IV challenge to tipifarnib. No biosimilar company is relevant because tipifarnib is a synthetic small molecule rather than a biologic.

The competitive threat comes primarily from alternative treatments for recurrent or metastatic HNSCC:

Competitor or class	Relevance to tipifarnib
Pembrolizumab	Established immunotherapy option in recurrent or metastatic HNSCC
Nivolumab	Established post-platinum immunotherapy option
Cetuximab	EGFR-targeted therapy with historical and combination use
Platinum-based chemotherapy	Relevant in earlier-line or combination treatment
Taxanes and methotrexate	Later-line systemic alternatives
Investigational HRAS-directed or RAS-pathway agents	Potential direct or mechanistic competition

Tipifarnib’s differentiation is its biomarker-based positioning. Its limitation is that only a small fraction of HNSCC patients may qualify.

What is the market projection for tipifarnib?

A realistic projection must separate addressable patients from commercial launch probability.

Patient population

The U.S. annual incidence of HNSCC is commonly estimated at more than 50,000 cases. Recurrent or metastatic disease represents a minority of cases, and HRAS mutations occur in a low single-digit percentage of HNSCC tumors. After accounting for advanced disease, prior platinum exposure, testing, performance status, and treatment access, the annual U.S. treatment-eligible population could plausibly fall in the low thousands or below.

A planning range is:

Market variable	Low case	Base case	High case
U.S. eligible patients annually	500	1,000	2,000
Net annual price	$80,000	$120,000	$160,000
U.S. addressable sales	$40 million	$120 million	$320 million
Probability of successful relaunch and approval	5%	15%	25%
Risk-adjusted U.S. value before operating costs	$2 million	$18 million	$80 million

These are scenario calculations, not company guidance or a consensus forecast. They exclude international pricing, discounts, testing costs, treatment duration differences, and commercial expenses.

A global opportunity could reach approximately $100 million to $500 million in annual gross sales if the drug gained approval in multiple markets and achieved broad testing adoption. The base-case commercial outlook remains below blockbuster scale because of the small biomarker-defined population.

Revenue exposure

Tipifarnib does not currently generate an established U.S. product revenue stream. Its value is therefore option-based. Revenue exposure depends on:

• Regulatory resubmission.
• Positive confirmatory efficacy data.
• HRAS testing adoption.
• Reimbursement for mutation testing.
• Competition from immunotherapy and targeted combinations.
• Partnership funding and commercial execution.

The asset’s value is more likely to be realized through a licensing transaction, regional partnership, or portfolio sale than through near-term standalone product revenue.

How does tipifarnib compare with competing targeted oncology drugs?

Attribute	Tipifarnib	Pembrolizumab	Cetuximab
Modality	Small-molecule oral inhibitor	Monoclonal antibody	Monoclonal antibody
Biomarker requirement	HRAS mutation intended	PD-L1 may guide use	No mandatory HRAS biomarker
HNSCC approval	None established	Approved	Approved
Patient population	Narrow	Broad	Broad
Administration	Oral	Intravenous	Intravenous
Patent position	Historic, uncertain current protection	Mature but substantial legacy estate	Mature and eroded
Regulatory risk	High	Low for established HNSCC use	Low for established HNSCC use
Commercial upside	Limited by biomarker frequency	Large	Established but mature

Tipifarnib could offer a targeted option for patients who lack effective alternatives, but it must overcome the incumbent therapies’ approval, reimbursement, and physician-adoption advantages.

What generic launch risks exist for tipifarnib?

The generic launch risk is unusual because patent risk is not currently the principal obstacle. The main risks are regulatory and commercial.

A future generic applicant would face:

1. No established approved reference product in the United States.
2. Uncertainty over whether the sponsor will obtain a new approval.
3. Possible later-filed method-of-use or formulation patents.
4. A small market that may not justify development cost.
5. Potential diagnostic requirements.
6. Limited physician demand outside HRAS-mutant disease.

If tipifarnib is approved and the market remains small, generic entry could still occur rapidly after the enforceable patent and regulatory exclusivity periods expire. The low patient count may discourage multiple entrants, but it could also make a first generic launch economically attractive if pricing remains high.

What licensing deals affect tipifarnib?

Kura Oncology acquired development rights to tipifarnib from Johnson & Johnson-related entities in 2014. That transaction enabled Kura to pursue a precision-oncology strategy centered on HRAS-mutant HNSCC.

No later licensing transaction has established a new commercial owner or a confirmed development partner for tipifarnib. The absence of a disclosed commercialization deal after the Complete Response Letter limits evidence of external validation.

A future transaction would likely be structured around one of three models:

• Regional licensing for Asia or Europe.
• Development partnership tied to confirmatory HRAS-mutant studies.
• Asset sale or option agreement after regulatory clarification.

Key Takeaways

• Tipifarnib is an oral farnesyltransferase inhibitor targeting HRAS-mutant cancers.
• Its leading indication is recurrent or metastatic HRAS-mutant HNSCC.
• The FDA granted Breakthrough Therapy designation but issued a Complete Response Letter in November 2021.
• Tipifarnib has no established FDA approval, commercial launch, Orange Book listing, or U.S. regulatory exclusivity.
• The clinical signal is meaningful, with reported response rates of about 55% and durable responses in a small Phase 2 population.
• The original composition patent estate is old, while current formulation and method-of-use protection is not publicly established as a decisive barrier.
• No major Paragraph IV challenge or biosimilar threat has been established.
• A realistic annual U.S. opportunity is likely in the tens to low hundreds of millions of dollars, not blockbuster territory.
• The most important value drivers are a credible FDA resubmission, confirmatory efficacy data, HRAS testing adoption, and a development or commercialization partner.

FAQs

Is tipifarnib approved for head and neck cancer?

No. Tipifarnib has not established FDA approval for HRAS-mutant HNSCC or another cancer indication.

Does tipifarnib have orphan-drug exclusivity?

No FDA orphan-drug exclusivity period has been established for an approved tipifarnib product.

Is tipifarnib a biosimilar or a generic biologic?

No. Tipifarnib is a synthetic small molecule administered orally and would follow the generic-drug pathway, not the biosimilar pathway.

What mutation is required for tipifarnib treatment?

The development program focuses on activating HRAS mutations, particularly in recurrent or metastatic HNSCC.

Could tipifarnib still become a commercial oncology product?

Yes, but commercialization would require renewed clinical development, a satisfactory FDA pathway, and evidence that the HRAS-mutant population is large and identifiable enough to support a profitable launch.

References

1. Ho, A. L., et al. (2021). Tipifarnib in head and neck squamous cell carcinoma with HRAS mutations: Results from the AIM-HN study. Journal of Clinical Oncology.

2. Kura Oncology, Inc. (2021, November 29). Kura Oncology receives complete response letter from FDA for tipifarnib NDA. Company press release.

3. Kura Oncology, Inc. (2024). Annual report on Form 10-K. U.S. Securities and Exchange Commission.

4. National Cancer Institute. (2024). Tipifarnib. NCI Drug Dictionary.

5. U.S. Food and Drug Administration. (2024). Orange Book: Approved drug products with therapeutic equivalence evaluations. FDA.

6. U.S. Food and Drug Administration. (2024). Breakthrough therapy designation. FDA.