Cialis history: approval, half-life, and later uses

What the 2003 letter actually approved

The approval letter for NDA 21-368 is dated in the signature block November 21, 2003. Florence Houn signed it at 10:33 a.m. The application itself was dated June 28, 2001, and received the next day. A complete response to an earlier action letter arrived May 27, 2003. The file was not a week-long stamp.

The letter says the application provides for Cialis (tadalafil) tablets for erectile dysfunction, and that it is approved as of the date of the letter for use as recommended in the agreed labeling. The sponsor on the address line is Lilly ICOS LLC, Lilly Research Laboratories, Indianapolis. Patients do not need the limited-liability paperwork. They do need to know the first US product was a Lilly ICOS erectile-dysfunction tablet, not a urinary drug and not a pulmonary-hypertension brand.

The 2003 printed labeling supplied three film-coated, almond-shaped yellow tablets, debossed C 5, C 10, and C 20, in bottles of 30. Those imprint codes are still how you recognize the Lilly strengths on the current label. Literature issued November 2003. Manufactured for Lilly ICOS LLC by Eli Lilly and Company.

FDA's talk paper the same day, T03-79, called Cialis the third oral medicine approved for this condition and said it stays in the body longer than the products already cleared. The agency described randomized, placebo-controlled trials in more than 4,000 men, including groups with diabetes and men who had undergone radical prostatectomy. Effectiveness was a questionnaire plus two practical reports: an erection adequate for intercourse, and an erection maintained long enough to finish. The current trial tables live on the evidence card. This page only keeps the year attached to the right question.

Why duration was the whole early argument

The current DailyMed Cialis label (setid bcd8f8ab-81a2-4891-83db-24a0b0e25895, revised March 2026) still gives the pharmacokinetic reason the 2003 talk paper was pointing at. In healthy subjects the mean terminal half-life is 17.5 hours. After a single oral dose, the peak arrives between 30 minutes and 6 hours, median 2 hours. Food does not meaningfully change the rate or extent of absorption.

A half-life that long makes a wide as-needed window plausible. It also makes a low daily dose chemically thinkable, because steady plasma levels are reached within 5 days and exposure is about 1.6 times the same milligram taken once. Thinkable is not the same as labeled. The 2003 letter approved the as-needed erectile-dysfunction use. The daily regimen waited for its own studies.

The approval letter also extracted a promise: a randomized, placebo-controlled study of color vision and retinal physiology after multiple daily doses, with a protocol due within 3 months and a final report within 18 months. That commitment is about the retina, not about a marketing calendar. The current label reports color-vision changes as rare, under 0.1% of patients across studies. Rare on a later label is not a rewrite of why the 2003 letter asked for the study.

An oral PDE5 inhibitor was already in US use before this approval. The sildenafil discovery note on this site carries that earlier story. Cialis is the slower member, filed by Lilly ICOS and cleared in November 2003, with duration as the difference FDA described in public that day.

The later jobs were new approvals, not fine print

On January 8, 2008, Eli Lilly announced that FDA had approved Cialis for once-daily use at 2.5 mg and 5 mg. The company described it as a tablet taken once a day so that sexual activity could be attempted between doses, and it pointed back to the 2003 as-needed approval, including the up-to-36-hour efficacy claim, as the older choice. Men were told, in that announcement, to pick a regimen with a physician. The announcement is a press release. The dosing rules you should follow are the ones on the current label, which the schedule card unpacks.

By the October 2011 label, the highlights listed recent major changes: benign prostatic hyperplasia in October 2011, and erectile dysfunction together with benign prostatic hyperplasia in the same month. Dosage-and-administration lines for those daily urinary uses were marked 10/2011 as well. The 5 mg stamp that had been an as-needed strength in 2003 now also carried a once-daily prostate job. Same imprint. Different indication. A man who takes 5 mg only on occasional nights is not on the urinary regimen the 2011 change described.

The current label's dosage-forms section still shows 5 mg, 10 mg, and 20 mg. The once-daily erectile-dysfunction start is still written as 2.5 mg, and the label says not to split tablets. History explains the pile-up. It does not authorize a kitchen half. A pharmacist has to match 2.5 mg to a product that is actually supplied.

Hypersensitivity on the current label names both Cialis and ADCIRCA. The patient information says Cialis is also marketed as ADCIRCA for pulmonary arterial hypertension, and not to take both. A serious reaction to either product rules out the other. Reading an erectile-dysfunction trial percentage onto a pulmonary regimen, or the reverse, mixes two approvals that happen to share an ingredient.

What this history will not sell

Search traffic that pairs Cialis with cheap, generic, or online is often a shopping question wearing a history word. Generic tadalafil is the same active ingredient when a licensed pharmacy dispenses it under a prescription. The 2003 letter does not set today's cash price, and this page will not invent one. The path that deals with online pharmacies is the compound page.

A second confusion is treating every 5 mg tablet as the 2008 or 2011 product. In 2003, 5 mg was one of three as-needed strengths. Once-daily 2.5 mg and 5 mg are a 2008 addition. Prostate-symptom use of 5 mg daily is a 2011 addition. If the bottle in the drawer is not labeled with the schedule, the imprint alone cannot tell those jobs apart.

Nitrates were already a hard stop in the first labeling, and they remain one. The long half-life that made the brand is also why the current label wants at least 48 hours after the last dose before a nitrate is even considered in a life-threatening situation, under monitoring. History does not soften that. Once-daily use, because levels are continuous, does not offer a weekend off as a workaround.

The useful end of the story is short. Cialis is tadalafil, first cleared in the United States on November 21, 2003, for erectile dysfunction as needed, because it lasted longer than the oral drugs already available. Daily dosing and prostate symptoms were later labeled uses of that same slow clearance. Your clinician still has to pick which of those uses, if any, is yours.

Questions the timeline still gets

When was Cialis approved? FDA approved NDA 21-368 on November 21, 2003, for erectile dysfunction. The current label's highlights still say initial U.S. approval 2003.

Who filed it? The approval letter is addressed to Lilly ICOS LLC. Eli Lilly and Company manufactured the tablets for that venture. The current DailyMed packager line is Eli Lilly and Company.

Was the first Cialis a daily tablet? No. The 2003 approval and the talk paper describe an erectile-dysfunction drug taken so that sex could follow a dose, with effect studied out toward 36 hours. Once-daily 2.5 mg and 5 mg were announced as approved on January 8, 2008.

When did prostate symptoms enter the label? The October 2011 highlights mark benign prostatic hyperplasia, and the combination with erectile dysfunction, as changes dated 10/2011. The dose is 5 mg once a day.

Is ADCIRCA the same prescription? It is tadalafil, named beside Cialis in the hypersensitivity contraindication, and it is approved for a different illness. Do not borrow erectile-dysfunction doses from it or the reverse.

Does the origin story include a price? No. For a licensed fill, use the compound card. For the trial arithmetic, use the evidence card.