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Sitavig Acyclovir 50 mg Tablet, Delayed Release, 2-count — NDC 71403-0049-02 package photo

Sitavig Acyclovir 50 mg Tablet, Delayed Release, 2-count

by EPI Health, Inc · 1 BLISTER PACK in 1 CARTON (71403-049-02) / 2 TABLET, DELAYED RELEASE in 1 BLISTER PACK
NDC 71403-0049-02
🏷️ FDA NDC (as labeled) 71403-049-02 billing pads the product segment with a zero
Rx only Brand Discontinued Non-controlled ⚠ Inactivated by FDA
🗂️ Data synced Jul 23, 2026 · sources: openFDA · FDA label (DailyMed) · FDA Orange & Purple Book · First Databank · CMS NADAC, ASP, Medicare & Medicaid · RxNorm
📋 All sources & update times →

This page is curated, coded, and maintained by

Compiled from public FDA, CMS, DailyMed, NADAC, and related drug data sources. Editorial policy

⚠️
Excluded from the active FDA NDC Directory. FDA inactivated this product’s listing record, so it is excluded from the active NDC Directory. The listing was last certified through Dec 2023. A label may still appear on DailyMed, but the NDC is no longer in the current FDA NDC Directory. Search the FDA NDC Directory ↗

🆔 Identity & classification

FDA NDC (as labeled) 71403-049-02
Product NDC 71403-049
11-digit billing NDC 71403004902
NCPDP billing unit EA — each (per item)
Application # NDA203791
SPL Set ID cd6e902d-5753-49ec-bec8-b27176ed978e
Established class (EPC) DNA Polymerase Inhibitors [MoA], Herpes Simplex Virus Nucleoside Analog DNA Polymerase Inhibitor [EPC], Herpes Zoster Virus Nucleoside Analog DNA Polymerase Inhibitor [EPC], Herpesvirus Nucleoside Analog DNA Polymerase Inhibitor [EPC], Nucleoside Analog [
DEA schedule Non-controlled
Marketing category NDA
Marketing status Discontinued
FDA listing status Inactivated by FDA (certified through Dec 2023)
Route BUCCAL
Dosage form TABLET, DELAYED RELEASE
Substance ACYCLOVIR
GCN Seq No 072344
GCN 36515
HICL code 004183
Ingredient (HICL) Acyclovir
HIC1 code W
Therapeutic class — broad (HIC1) Anti-Infecting Agents
HIC2 code W5
Therapeutic class — intermediate (HIC2) Antiviral Agents
HIC3 code W5A
Therapeutic class — specific (HIC3) Antivirals, General
AHFS code 08:18.32.00
AHFS class Nucleoside And Nucleotide Antivirals
FDB label name SITAVIG 50 MG BUCCAL TABLET
FDB brand name Sitavig
Legend status F — Federal legend — prescription drug or device
Why two NDCs? The FDA registers this code as 71403-049-02 — a 5-3-2 layout, and that's what's printed on the package and shown on DailyMed. For insurance claims, every NDC is standardized to a uniform 11-digit 5-4-2 format by adding a zero to the product segment → 71403-0049-02. Same drug, same package — only the format differs.
Where does this data come from?
Identifiers from the FDA openFDA NDC Directory and Structured Product Labeling; RxCUI from RxNorm (NLM); GPI from Medi-Span; GCN / HIC / AHFS / legend from First Databank.

🏭 Manufacturer & labeler

LabelerEPI Health, Inc
Application holderLIGAND PHARMACEUTICALS INC
FDA applicationNDA203791 (NDA)
Labeler code71403
Product typeHuman Prescription Drug
The labeler markets the product; the application holder owns the FDA approval. They’re often the same company but can differ (e.g. a repackager or an authorized generic). A mailing address / phone appears here when the manufacturer includes it in the product’s FDA label (not all do).
Where does this data come from?
Labeler, application holder and registered establishment from the FDA openFDA NDC Directory and Drugs@FDA; address/contact from the product’s FDA label.

🩺 Clinical

Label name SITAVIG 50 MG BUCCAL TABLET Ingredient Acyclovir
📖 What it is MedlinePlus · NLM

Acyclovir is used to treat viral infections like chickenpox, herpes zoster (shingles) and genital herpes (a sexually transmitted disease). Acyclovir is in a class of medications called antivirals. It works by stopping the spread of the virus in the body.  Acyclovir will not cure herpes infections and may not stop the spread of herpes virus to other people.

Read the full MedlinePlus article ↗
📗 Our plain-language guide HelloPharmacist
  • Acyclovir doesn't cure herpes — it can't eliminate the virus from your body. What it does is slow down the virus's ability to copy itself, which shortens outbreaks, eases symptoms,...
  • What exactly does acyclovir do — does it cure herpes?
  • Timing really does matter with acyclovir. For cold sores, you want to start at the very first warning sign — that tingling or itching feeling — before a sore even appears. For geni...
  • How soon do I need to start taking it for it to work?
📖 Read our full Acyclovir guide →
Where does this data come from?
Plain-language summary from MedlinePlus (U.S. National Library of Medicine); supplement & herbal interactions and nutrient depletion data from the Natural Medicines database; our full guide is HelloPharmacist editorial content.

💊 What it looks like

Color white
ShapeRound
ImprintAL21
Size8 mm
ScoringNot scored
One label can cover several strengths, so colors may be combined — always confirm a loose pill against the dispensed prescription label or a pharmacist.
Where does this data come from?
Physical description (imprint, shape, color, scoring, coating) from this product’s FDA Structured Product Labeling (SPL), mirrored from DailyMed / openFDA.

🧪 Inactive Ingredients / Excipients

Inactive ingredients, also called excipients, are components of the drug product other than the active ingredient. They may include fillers, dyes, coatings, preservatives, flavors, or other formulation ingredients.

💡 Tap an ingredient (hover on desktop) to see what it is and why it’s used.

  • UNII Z78RG6M2N2
    Hypromellose 2208 is a plant-derived thickening agent used as a binder and film-coating material in tablets and capsules. It helps hold ingredients together and creates a protective coating that controls how quickly the medicine dissolves.
  • UNII 70097M6I30
    Magnesium stearate is a salt made from magnesium and stearic acid, a fatty substance. It's used in tablets and capsules as a lubricant and glidant to help ingredients flow smoothly during manufacturing and prevent sticking.
  • UNII OP1R32D61U
    Microcrystalline cellulose is a purified form of cellulose, a natural fiber from plant sources. It acts as a binder and filler in tablets and capsules, helping hold ingredients together and give the medicine its shape and size.
  • UNII FZ989GH94E
    Povidone is a synthetic polymer made from a plastic-like material. It acts as a binder to hold tablet ingredients together and as a disintegrant to help the tablet break apart in your stomach so the medicine can be absorbed.
  • UNII ETJ7Z6XBU4
    Silicon dioxide is a naturally occurring mineral used as a glidant and anti-caking agent. It helps powder ingredients flow smoothly and prevents clumping during manufacturing and storage.
  • UNII 368GB5141J
    A detergent and foaming agent derived from coconut or palm oil. In medications, it helps break down and mix oil and water-based ingredients, aids in tablet disintegration, and improves how the drug dissolves and spreads in the mouth or digestive system.
  • UNII 059QF0KO0R
    Water is a liquid solvent that dissolves and mixes ingredients together in liquid medicines, syrups, and injections. It helps distribute the active drug evenly throughout the product.

7 inactive ingredients listed in the exact product block matched to this NDC.

Where does this data come from?
Data sourced from official FDA Structured Product Labeling (SPL) via DailyMed — ingredient classCode="IACT" elements from the exact product block matched by this NDC. Label-section narrative from DailyMed / the openFDA label index is shown separately when available.

Inactive ingredient FAQ

Are inactive ingredients the same for every manufacturer?
No. Inactive ingredients can differ by manufacturer, dosage form, strength, and package / product version.
Why might an inactive ingredient be missing?
Some SPLs do not provide a complete structured inactive-ingredient list, and older or unusual labels may only include the information in narrative text.
Can inactive ingredients matter?
Yes. They can matter for allergies, intolerances, dyes, gluten / lactose concerns, preservatives, and formulation differences — but confirm with a pharmacist or the manufacturer when it’s clinically important.

💲 Pricing

A drug doesn't have one price. Each row is a different public payment system, and none is what you'd pay at the counter — that depends on your insurance. The ⓘ on each row explains what it measures.

Price systemPer eachPer package
Retail pharmacies payNADAC · weekly Not in the retail survey — common for institutional, discontinued, or low-volume packs.
Medicaid paysCMS SDUD · 12 mo No recent Medicaid claims on file for this NDC — rare and low-volume NDCs are suppressed in the public data.
Medicare drug plans payPart D · quarterly No Part D plan price is available for this NDC in our data.
ℹ️
No price is published for this exact package yet. CMS surveys NADAC per package size, so a different pack of the same drug often has one.
Where does this data come from?
NADAC (National Average Drug Acquisition Cost) is the CMS weekly pharmacy-acquisition-cost survey — what pharmacies pay. ASP (Average Sales Price) is the CMS Medicare Part B drug-payment file, published quarterly. Medicaid pays is computed by us from CMS State Drug Utilization Data (total reimbursed ÷ units, trailing 12 months) — gross of rebates and inclusive of dispensing fees, so it reflects what Medicaid paid, not an acquisition cost. Medicare drug plans pay is the median negotiated point-of-sale unit cost across plans listing this NDC in the CMS quarterly Prescription Drug Plan pricing files, before rebates. The VA pays is the federal contract price (FSS, and the statutory Big 4 ceiling where listed) from the VA National Acquisition Center pharmaceutical price file. All are free public government data; each measures a different payer, so the figures are not directly comparable.

🔁 Therapeutic equivalents

ProductLabelerPackNADAC/unitTEStatusPrice vs. this
Sitavig 50 mgthis 71403-0049-02 EPI 2 tablets — — Discontinued —
About this product: this is the brand-name version. We did not find an FDA-approved generic match for this exact strength, form and route.
Where does this data come from?
Equivalents are other NDCs of the same ingredient, form and route from the openFDA NDC Directory, ranked least-expensive-first by NADAC. Therapeutic-equivalence (AB) ratings come from the FDA Orange Book; biologics use the FDA Purple Book for biosimilar & interchangeable status.

⏳ Availability & generic status

🏛️
2013
First FDA approval
Apr 2013
📍
2026
Currently FDA-listed
13 years listed
🛡️
2030
Latest patent/protection listed
not a guaranteed launch date
🔒No FDA-approved generic found

We did not find an FDA-approved generic match for this exact strength, form and route. Patent/protection dates below may affect future generic timing.

🛡️ Latest patent/protection date listed: FDA patent/protection data lists protections through Jun 2030. This may affect when a full generic version becomes widely available, but it is not a guaranteed launch date.
📅 FDA approved Apr 12, 2013 RLD RS ⏳ ~3.7 yr to latest listed protection

Why the date isn’t exact: Generic timing can change because patents may be challenged, settled, licensed, added, removed, or worked around with a narrower label — and FDA approval does not always mean a pharmacy can get the generic today.

Patents & exclusivity — FDA Orange Book
US 8747896 — method of use (U-1460)
US 8592434 — method of use (U-1460)
US 8791127 — method of use (U-1460)
2013 2015 2017 2019 2021 2023 2025 2027 2029
Today
LOE
Substance patent Formulation patent Method-of-use patent Exclusivity Pediatric +6mo
🏛️FDA exclusivity
FDA-granted marketing protection. It’s separate from patents and may be shorter than patent protection.
🧪Product / substance patents
Patents covering the active ingredient, product, formulation, or related drug features.
🎯Method-of-use patents
Patents covering specific approved uses. These can sometimes be carved out with a “skinny label,” but not always.
🛈 What do these terms mean?
Patent
Legal protection listed in the Orange Book that may delay generic approval or launch. Issued by the U.S. Patent & Trademark Office.
Substance patent
Covers the active drug molecule itself — the hardest to design around. A generic generally can’t launch until it expires.
Formulation (product) patent
Covers a specific formulation or dosage form. A generic can sometimes work around it with a different formulation.
Method-of-use patent
A patent covering one specific approved use of the drug — not necessarily the whole molecule. A generic can sometimes launch with a “skinny label” that carves out the protected use and keeps the others.
Skinny label
A generic label that omits a still-patented use when the FDA allows it — letting a generic reach the market for the unprotected uses.
Exclusivity
FDA-granted marketing protection, separate from patents — e.g. 5-yr new chemical entity, 7-yr orphan drug, or a +6-month pediatric extension.
Paragraph IV
A generic applicant’s formal challenge to a listed patent. It can potentially lead to earlier generic entry, but often involves litigation or a settlement.
RLD / RS
Reference Listed Drug — the brand product the FDA uses as the reference for generic applications. Reference Standard — the product the FDA expects generics to compare against in bioequivalence testing.
TE / AB rating
FDA therapeutic-equivalence rating. An AB rating generally means the FDA considers a generic therapeutically equivalent to — and substitutable for — the brand.
LOE (loss of exclusivity)
The latest patent or exclusivity currently listed — the loss-of-exclusivity / latest-listed-protection date shown on this page. Paragraph-IV challenges and settlements can move the real date earlier; FDA approval and a manufacturer’s decision to market can move it later.

Built from the FDA Orange Book. The bars above are scaled to each protection’s expiry; the red LOE marker is the last one to lapse.

Listed patents (3)
PatentTypeUse codeExpires
US 8747896 ↗ Method of use U-1460 Jun 3, 2027
US 8592434 ↗ Method of use U-1460 Jun 16, 2030
US 8791127 ↗ Method of use U-1460 Mar 23, 2027
Common questions
Is there a generic version of SITAVIG 50 MG BUCCAL TABLET?
No FDA-approved generic equivalent is currently listed in the FDA Orange Book for SITAVIG 50 MG BUCCAL TABLET. Based on the patents and exclusivity currently listed, the Orange Book estimate is that full-label generic entry may be delayed until Jun 2030 — an estimate, not a guaranteed launch date.
The FDA approved a generic — why can’t I get it at my pharmacy yet?
FDA approval and pharmacy availability are two different things. The FDA can approve a generic years before it actually reaches pharmacies, because the brand company may still hold patents or have a settlement that delays the launch. A manufacturer also has to choose to make and sell it, and have supply ready. So a drug can be “FDA-approved generic exists” and still be brand-only at the counter today.
Why do different websites show different generic release dates?
Generic availability is not based on one single date. Some sources use the first exclusivity expiration, some use the last product patent, and others use the latest method-of-use patent. Patent challenges, settlements, licenses, and label carve-outs can also change the real-world launch date. This page shows the underlying Orange Book dates so you can see why estimates may differ.
What does “FDA listed” mean?
It means the product appears in the FDA’s official NDC directory. That’s a good sign a product exists and is intended for the U.S. market, but on its own it does not confirm a pharmacy can fill it today. Where we have recent retail pricing data (NADAC) for a product, we label it “Availability likely” instead.
What does a patent or protection date mean here?
It’s the latest date currently listed in the FDA Orange Book for a patent or exclusivity on the brand product. It can affect when a full generic version becomes widely available — but it is not a guaranteed generic launch date. Generics sometimes arrive earlier (through a settlement or patent challenge) or later (a manufacturer still has to make and sell one).
What does “current Orange Book estimate” mean?
It means we are using the latest patent and exclusivity dates currently listed in the FDA Orange Book. It is not a guaranteed launch date.
Can a generic come out before the last patent expires?
Sometimes. A generic company may challenge a patent, settle with the brand manufacturer, receive a license, or obtain approval with a narrower label that avoids a patented use. In other cases, the last listed protection may delay full-label generic competition.
Can a generic come out after the listed dates?
Yes. Even after patents or exclusivity expire, a generic still needs FDA approval and a manufacturer must choose to market it. Supply, litigation, business decisions, or regulatory issues can delay actual availability.
What is the difference between patents and exclusivity?
Patents are legal protections usually issued by the U.S. Patent and Trademark Office. FDA exclusivity is marketing protection granted by the FDA. They are separate, and either one can affect generic timing.
Why are there multiple patent dates?
One drug can have several patents covering different things: the active ingredient, a formulation, a manufacturing process, or a specific approved use. That is why a page may show several expiration dates instead of one simple generic date.
Built from FDA Orange Book patent and exclusivity data. Dates are refreshed from public FDA data when available; the marker is max(latest patent expiry, latest exclusivity expiry). Paragraph-IV settlements and first-filer 180-day exclusivity can shift the real date; a method-of-use patent may allow an earlier skinny-label generic for non-protected indications. Generic launch timing is an estimate, not a guarantee.
Where does this data come from?
Patents and exclusivity from the FDA Orange Book (small-molecule drugs), refreshed from public FDA data. Generic launch timing is an estimate, not a guarantee.

📊 Medicare Part D spend CMS · PART D · 2026 (Q1)

Medicare Part D (outpatient prescription) spending for Acyclovir (matched by generic name) — the program that covers self-administered drugs. 29 manufacturers.
⚠️ Drug-level data: CMS publishes Part D spending by drug, not by NDC — these figures combine every manufacturer, strength and package size sold under the name Acyclovir. CMS lists 2 products for this generic; we show the highest-spend one. That’s a different level of aggregation than the Medicaid card above, which is specific to this exact 11-digit NDC (pack size included), so the two aren’t directly comparable.
Period
Total Part D spend
$11.1M
Claims incl. refills
517.4K
Beneficiaries
366.8K
Spend / beneficiary
$30.28
Spend / claim
$21.46
Trend by period
💵 About the dollar figures: spending is what Part D plans paid before confidential manufacturer rebates, so the program’s real net cost is lower. A blank patient count means fewer than 11 people — CMS hides counts that small to protect privacy. Source: CMS Medicare Quarterly Part D Spending by Drug (data.cms.gov), updated quarterly.

📦 Packaging — all sizes for this product

Package NDCDescription Marketing startStatus
71403-0049-02 You're viewing this 1 BLISTER PACK in 1 CARTON (71403-049-02) / 2 TABLET, DELAYED RELEASE in 1 BLISTER PACK 2014-03-20 Inactivated by FDA

🧭 About this NDC listing & data coverage

Finished prescription product No longer marketed (per FDA listing data)
What data is (and isn’t) available for this NDC — tap to expand
NDC identity (package / product / labeler codes) ✓ Available
Labeler ✓ Available
Product & package description ✓ Available
Marketing category & status ✓ Available
Active ingredient / dosage form / route ✓ Available
FDA label (SPL via DailyMed) ✓ Available
Package photos ✓ Available
Inactive ingredients (structured) ✓ Available
NADAC pharmacy acquisition price (CMS) — Not published for this NDC CMS publishes NADAC only for NDCs reported in its retail-pharmacy survey.
Orange Book / therapeutic-equivalence data ✓ Available
HCPCS J-code billing crosswalk — Not published for this NDC Most self-administered / retail products have no J-code — that is normal.
Medicaid utilization (CMS SDUD) — Not published for this NDC CMS reports utilization only for NDCs with Medicaid claims above its privacy threshold.
“Not published” reflects what the public FDA / CMS / NLM sources provide for this exact package code — it is a property of the data feeds, not a judgment about the product.

Questions about this listing

Why is there no price listed?
The pricing shown on our NDC pages comes from CMS NADAC, a voluntary survey of retail community pharmacy invoices. CMS does not publish a NADAC for every NDC — packages outside the retail survey (institutional and hospital products, bulk packages, discontinued items, and many OTC items) may never receive one. A missing price reflects the survey's scope, not this product's actual cost, and does not mean the product is free or unavailable.
What does the discontinued status mean for this NDC?
The labeler reported a marketing end date (or the listing was delisted), so this specific package is no longer actively marketed. Remaining stock may still be dispensed for a time, and the NDC stays valid for historical records and claims — but data feeds (pricing, labeling) typically stop updating for it. Other package sizes or other manufacturers' versions of the same medication may still be marketed — see the equivalents section where available.
Is the NDC printed on the package the same as the 11-digit billing NDC?
Yes, they identify this exact package in different formats. The FDA registers it as 71403-049-02, which is what is printed on the packaging and shown on DailyMed. Insurance claims use a fixed 11-digit 5-4-2 format, so the short segment is padded with a leading zero: 71403-0049-02, written without dashes as 71403004902. The Identity section at the top of this page lists every form of this code.
What do the three segments of this NDC mean?
In 71403-0049-02, the first segment (71403) is the labeler code FDA assigned to EPI Health, Inc; the middle segment (0049) identifies this specific product — its ingredient, strength, and dosage form; and the last segment (02) identifies this exact package size and type. Together they name one specific package of one specific product.
Who lists this product with the FDA?
EPI Health, Inc is the labeler of record for this NDC — the company under whose FDA-assigned code the package is listed. The labeler may be the manufacturer itself or a distributor marketing the product under its own code.
Do I need a prescription for this product?
This NDC is listed with FDA as a prescription product, so it is dispensed under a prescriber's order. Your pharmacist can tell you whether any over-the-counter forms of the same medication exist.
This page identifies an FDA-listed package (the NDC) and reports public regulatory and pricing data about the listing. It is reference information, not a medical recommendation — talk to your pharmacist or prescriber about your own medication.
Where does this data come from?
Listing facts (marketing category, packager status, marketing dates) from the FDA openFDA NDC Directory; label availability from DailyMed; pricing coverage from CMS NADAC; equivalence scope from the FDA Orange Book.

📄 Full prescribing information FDA SPL

The complete FDA label for this product — the official prescribing information, verbatim, section by section. Jump with a chip, search within the label, or expand everything.
🎯 Indications and Usage ⏱️ Dosage and Administration 💊 Dosage Forms and Strengths ⛔ Contraindications 🤒 Adverse Reactions 🔄 Drug Interactions 👥 Use in Specific Populations 🤰 Pregnancy 🧒 Pediatric Use 🧓 Geriatric Use 🆘 Overdosage 🧬 Clinical Pharmacology 🧬 Mechanism of Action 📦 How Supplied / Storage and Handling 📦 Storage and Handling 📋 Description 💬 Information for Patients
🎯 Indications and Usage 44 words ▾

1 INDICATIONS AND USAGE SITAVIG is indicated for the treatment of recurrent herpes labialis (cold sores) in immunocompetent adults. SITAVIG is a deoxynucleoside analogue of DNA polymerase inhibitor, indicated for the treatment of recurrent herpes labialis (cold sores) in immunocompetent adults. ( 1 ).

⏱️ Dosage and Administration ~2 min read ▾

2 DOSAGE AND ADMINISTRATION Application of one SITAVIG 50 mg buccal tablet as a single dose to the upper gum (canine fossa) region ( 2.1 ). SITAVIG should be applied within one hour after the onset of prodromal symptoms and before the appearance of any signs of herpes labialis. Do not crush, chew, suck or swallow tablets ( 2.2 ).

2.1Basic Dosing Information One SITAVIG 50 mg buccal tablet should be applied as a single dose to the upper gum region (canine fossa).

2.2Administration Instructions SITAVIG should be applied within one hour after the onset of prodromal symptoms and before the appearance of any signs of herpes labialis lesions. The tablet should be applied with a dry finger immediately after taking it out of the blister. The tablet should be placed to the upper gum just above the incisor tooth (canine fossa) and held in place with a slight pressure over the upper lip for 30 seconds to ensure adhesion.

For comfort the rounded side should be placed to the upper gum, but either side of the tablet can be applied. Tablet should be applied on the same side of the mouth as the herpes labialis symptoms. Once applied, SITAVIG stays in position and gradually dissolves during the day. [See Clinical Pharmacology (12.3) ].

In addition, SITAVIG should not be crushed, chewed, sucked or swallowed. Food and drink can be taken normally when SITAVIG is in place. Avoid any situations which may interfere with adhesion of the tablet such as chewing gum, touching or pressing the tablet after placement, wearing upper dentures, and brushing teeth.

If the teeth need to be cleaned while the tablet is in place, rinse the mouth gently. Drink plenty of liquids in the case of dry mouth. If SITAVIG does not adhere or falls off within the first 6 hours , the same tablet should be repositioned immediately.

If the tablet cannot be repositioned, a new tablet should be placed. If SITAVIG is swallowed within the first 6 hours , the patient should drink a glass of water and a new tablet should be applied. [see Patient Counseling Information (17) ]. SITAVIG does not need to be reapplied if the tablet falls out or is swallowed after the first 6 hours.

💊 Dosage Forms and Strengths 47 words ▾

3 DOSAGE FORMS AND STRENGTHS SITAVIG is a buccal tablet containing 50 mg of acyclovir. SITAVIG tablets are round, off-white tablets, with a rounded side and a flat side. The tablets are marked with an "AL21" on the flat side. 50 mg buccal tablets ( 3 ).

⛔ Contraindications 41 words ▾

4 CONTRAINDICATIONS SITAVIG is contraindicated in patients with known hypersensitivity (e.g., anaphylaxis) to acyclovir, milk protein concentrate, or any other component of the product. Known hypersensitivity to acyclovir, milk protein concentrate, or any other component of the product ( 4 ).

🤒 Adverse Reactions ~1 min read ▾

6 ADVERSE REACTIONS Most common adverse reactions (≥1%) are: headache and application site pain ( 6.1 ). To report SUSPECTED ADVERSE REACTIONS, contact EPI Health, LLC at 1-800-499-4468 or FDA at 1-800-FDA-1088 or www.fda.gov/medwatch.

6.1Clinical Trial Experience Because clinical trials are conducted under widely varying conditions, adverse reaction rates observed in the clinical trials of a drug cannot be directly compared to rates in the clinical trials of another drug and may not reflect the rates observed in clinical practice. The overall safety of SITAVIG was assessed in 378 adult subjects having at least 4 herpes labialis episodes the previous year. One randomized, double-blind, placebo controlled trial was conducted in patients with recurrent herpes labialis (cold sores).

In this trial, 378 HSV infected subjects used SITAVIG as a single dose, and 397 subjects used placebo. Selected treatment emergent adverse events without regard to causality and reported in at least 1% of patients can be seen in Table 1. Table 1: Selected Treatment Emergent Adverse Events reported in at least 1% of patients Event SITAVIG N = 378 Placebo N = 397 Nervous System Disorders Headache 3% 3% Dizziness 1% 1% Lethargy 1% 0 Gastrointestinal system Disorders Gingival Pain 1% 0.3% Aphthous Stomatitis 1% 0 Administration Site Conditions Application Site Pain 1% 1% Application Site Irritation 1% 0 Skin and Subcutaneous Disorders Erythema 1% 0.3% Rash 1% 0.3% The treatment emergent adverse events considered related to treatment that occurred in greater than or equal to 1% of patients included headache (1% SITAVIG vs.

2% placebo) and application site pain (1% both arms). There was no discontinuation of SITAVIG due to adverse drug reactions. Most treatment related adverse events were mild or moderate in severity.

One report of headache from both treatment arms was classified as severe.

🔄 Drug Interactions 71 words ▾

7 DRUG INTERACTIONS No interaction studies have been performed with SITAVIG. Acyclovir is primarily eliminated unchanged in the urine via active tubular secretion. Drugs administered concomitantly that compete with tubular secretion may increase acyclovir plasma concentrations.

However, due to the low dose and minimal systemic absorption of SITAVIG, systemic drug interactions are unlikely. Due to the low dose and minimal systemic absorption of SITAVIG, drug interactions are unlikely ( 7 )

👥 Use in Specific Populations ~1 min read ▾

8 USE IN SPECIFIC POPULATIONS

8.1Pregnancy There are no available data on SITAVIG use in pregnant women. However, published observational studies over decades of use of acyclovir have not identified a drug-associated risk of major birth defects, miscarriage, or adverse maternal or fetal outcomes. Systemic exposure of acyclovir following buccal administration of SITAVIG is minimal [see Clinical Pharmacology (12.3) ] .

Animal reproduction studies have not been conducted with SITAVIG. Animal reproduction studies with systemic exposure of acyclovir have been conducted. Refer to oral and parental acyclovir prescribing information for additional details.

8.2Lactation There are no data on the presence of acyclovir in human milk following buccal administration. There are no data on the effects of acyclovir on the breastfed infant or milk production. Systemic exposure following buccal administration of acyclovir is minimal [see Clinical Pharmacology (12.3) ] .

The developmental and health benefits of breastfeeding should be considered along with the mother's clinical need for SITAVIG and any potential adverse effects on the breastfed child from SITAVIG or from the underlying maternal condition.

8.4Pediatric Use Safety and effectiveness of SITAVIG in pediatric patients have not been established. The ability of pediatric patients to comply with the application instructions has not been evaluated. Use in younger children is not recommended due to potential risk of choking.

8.5Geriatric Use Clinical studies of SITAVIG did not include sufficient numbers of subjects aged 65 and over to determine whether they respond differently from younger subjects.

8.6Immunocompromised Patients The safety of SITAVIG has not been studied in immunocompromised subjects.

🤰 Pregnancy 88 words ▾

8.1Pregnancy There are no available data on SITAVIG use in pregnant women. However, published observational studies over decades of use of acyclovir have not identified a drug-associated risk of major birth defects, miscarriage, or adverse maternal or fetal outcomes. Systemic exposure of acyclovir following buccal administration of SITAVIG is minimal [see Clinical Pharmacology (12.3) ] .

Animal reproduction studies have not been conducted with SITAVIG. Animal reproduction studies with systemic exposure of acyclovir have been conducted. Refer to oral and parental acyclovir prescribing information for additional details.

🧒 Pediatric Use 43 words ▾

8.4Pediatric Use Safety and effectiveness of SITAVIG in pediatric patients have not been established. The ability of pediatric patients to comply with the application instructions has not been evaluated. Use in younger children is not recommended due to potential risk of choking.

🧓 Geriatric Use 27 words ▾

8.5Geriatric Use Clinical studies of SITAVIG did not include sufficient numbers of subjects aged 65 and over to determine whether they respond differently from younger subjects.

🆘 Overdosage 31 words ▾

10 OVERDOSAGE Acyclovir absorption and systemic exposure following application of SITAVIG are minimal. Overdose is therefore unlikely [see Clinical Pharmacology (12.3) ]. Symptomatic and supportive care is the basis for management.

🧬 Clinical Pharmacology ~3 min read ▾

12 CLINICAL PHARMACOLOGY

12.1Mechanism of Action Acyclovir is an antiviral drug active against α-herpesviruses [see Microbiology (12.4) ] .

12.3Pharmacokinetics Absorption and Distribution Salivary The pharmacokinetic parameters of acyclovir after a single dose of SITAVIG in the saliva and plasma of healthy volunteers are provided in Table 2. Table 2: Pharmacokinetic (PK) Parameters of Acyclovir in Saliva and Plasma Following Application of a Single SITAVIG 50 mg Tablet in Healthy Volunteers (N = 12) PK Parameters (N = 12) Salivary Mean ±SD (Min - Max) Plasma Acyclovir plasma concentrations had a delayed appearance (undetectable at 5 hours) and were below the concentrations required for antiviral activity (range: 17.5 to 55.3 nanogram per mL).

Mean ±SD (Min - Max) AUC 0-24h (mcg∙h/mL) 2900 ± 2400 (849 - 9450) 0.225 + 0.132 (0.027-0.422) C max (mcg/mL) 440 ± 241 (149 – 959) 0.028 + 0.010 (0.017-0.055) T max (hour) Median (Min – Max). 7.04 (3.07 – 18.05) 12 (5-16) In the Phase 3 study, the levels of acyclovir in saliva were measured within 24 hours of SITAVIG application in 56 patients with recurrent herpes labialis (mean value 88.1 micrograms per mL) and were within the range of those observed in the PK study in healthy volunteers. In healthy volunteers, the median duration of buccal adhesion was 14 hours following application of a single SITAVIG 50 mg tablet.

Plasma Plasma concentrations of acyclovir were measured in 12 healthy volunteers after a singledose application of SITAVIG 50 mg buccal tablet. Acyclovir concentrations had a delayed appearance (undetectable at 5 hours) and were below the concentrations required for antiviral activity (range: 17.5 to 55.3 nanogram per mL). Metabolism and Excretion Acyclovir is metabolized to 9-[(carboxymethoxy)methyl]guanine (CMMG) and 8-hydroxy-acyclovir (8-OH-ACV) by oxidation and hydroxylation, and is primarily excreted unchanged by the kidneys.

Food Effect There was no formal food effect study conducted with SITAVIG; however, in clinical studies patients were allowed to eat and drink while taking SITAVIG.

12.4Microbiology Mechanism of Action Acyclovir is a synthetic purine deoxynucleoside analogue with inhibitory activity against herpes simplex viruses type 1 (HSV-1) and type 2 (HSV-2) DNA polymerases. It inhibits HSV-1 and HSV-2 replication in cell culture and in vivo . The inhibitory activity of acyclovir is selective due to its affinity for the enzyme thymidine kinase encoded by HSV.

This viral enzyme converts acyclovir into acyclovir monophosphate, a deoxynucleotide analogue. The monophosphate is further converted into diphosphate by cellular guanylate kinase and into triphosphate by a number of cellular enzymes. In biochemical assays, acyclovir triphosphate inhibits replication of α-herpes viral DNA.

This inhibition is accomplished in 3 ways: 1) competitive inhibition of viral DNA polymerase, 2) incorporation into and termination of the growing viral DNA chain, and 3) inactivation of the viral DNA polymerase. Antiviral activity The quantitative relationship between the susceptibility of herpes viruses to antivirals in cell culture and the clinical response to therapy has not been established in humans, and virus sensitivity testing has not been standardized. Sensitivity testing results, expressed as the concentration of drug required to inhibit by 50% the growth of virus in cell culture (EC 50 ), vary greatly depending upon a number of factors.

Using plaque-reduction assays on Vero cells, the EC 50 values of acyclovir against herpes virus isolates ranged from 0.09 to 60 µM (0.02 to 13.5 µg/mL) for HSV-1 and from 0.04 to 44 µM (0.01 to 9.9 μg/mL) for HSV-2. Resistance In Cell Culture Acyclovir-resistant HSV-1 and HSV-2 strains were isolated in cell culture. Acyclovirresistant HSV resulted from mutations in the viral thymidine kinase (TK; pUL23) and DNA polymerase (POL; pUL30) genes.

Frameshifts were commonly isolated and result in premature truncation of the HSV TK product with…

🧬 Mechanism of Action 17 words ▾

12.1Mechanism of Action Acyclovir is an antiviral drug active against α-herpesviruses [see Microbiology (12.4) ] .

📦 How Supplied / Storage and Handling 83 words ▾

16 HOW SUPPLIED/STORAGE AND HANDLING SITAVIG buccal tablets are supplied as off-white tablets containing 50 mg of acyclovir. SITAVIG tablets have a rounded side and a flat side and are imprinted with AL21 on one side. SITAVIG tablets are packaged in blisters of two tablets (NDC 71403-049-02).

SITAVIG should be stored at 20 to 25°C (68 to 77°F) [see USP controlled room temperature]; excursions between 15 and 30°C (59-86°F) permitted at room temperature. Protect from moisture and keep out of reach of children.

📦 Storage and Handling 36 words ▾

SITAVIG should be stored at 20 to 25°C (68 to 77°F) [see USP controlled room temperature]; excursions between 15 and 30°C (59-86°F) permitted at room temperature. Protect from moisture and keep out of reach of children.

📋 Description 124 words ▾

11 DESCRIPTION SITAVIG (acyclovir) buccal tablet is applied topically to the gum and releases acyclovir as the buccal tablet gradually dissolves [see Clinical Pharmacology (12.3) ]. Acyclovir is a synthetic purine nucleoside analogue active against herpes viruses. The chemical name of acyclovir is 2-amino-1,9-dihydro-9-[(2-hydroxyethoxy)methyl]-6H-purin-6-one; it has a molecular formula of C 8 H 11 N 5 O 3 and a molecular weight of 225.

The structural formula is shown in Figure 1. Figure 1: Structural Formula of Acyclovir Acyclovir drug substance is a white or almost white crystalline powder. SITAVIG contains 50 mg of acyclovir, USP and the following inactive ingredients: hypromellose, USP; milk protein concentrate; sodium lauryl sulfate, NF; magnesium stearate, NF; microcrystalline cellulose, NF; povidone, USP; colloidal silicon dioxide, NF.

Chemical Structure

💬 Information for Patients ~1 min read ▾

17 PATIENT COUNSELING INFORMATION See FDA-approved patient labeling ( Patient Information and Instructions for Use ).

17.1Instructions for Use Read the Instructions for Use that comes with SITAVIG before you start using it. Talk to your doctor or pharmacist if you have any questions. Important: SITAVIG should be applied to the area of the upper gum above the incisor tooth.

SITAVIG tablets should not be crushed, sucked, chewed or swallowed. If it comes out before 6 hours have gone by, reapply it. If this does not work then a new tablet should be applied.

It should not be applied to the inside of the lip or cheek. Tablet should be applied on the same side of the mouth as the herpes labialis symptoms. Do not remove SITAVIG if it sticks to your upper gum.

If SITAVIG does not stick or falls off of your upper gum within the first 6 hours that you apply it, place it back onto your upper gum. If it still does not stick, replace it with a new SITAVIG tablet. Do not re-apply SITAVIG if it falls out or you swallow it after it has been in place 6 hours or longer.

If you swallow SITAVIG within the first 6 hours of applying it, drink a glass of water and place a new SITAVIG tablet onto your upper gum.

17.2Adverse Reactions Patients may experience adverse reactions including headache, and application site pain.

Source: FDA Structured Product Labeling, mirrored from DailyMed / openFDA. Prefer the government’s original formatting? View this label on DailyMed ↗
← 71403-0003-15 · EPI 71408-0001-01 · Ineos →
For educational and professional reference only — not medical advice. Pricing reflects published NADAC and CMS ASP (free public data) and may differ from your acquisition cost; always verify before billing or dispensing.