FDA aims to act on a standard prior approval supplement in 6 months, or 10 months if the agency must inspect a site first [1]. That is the short part of qualifying a second source. Tech transfer, registration batches and stability data must come before the filing. When we add those steps, a second active pharmaceutical ingredient (API) source takes between 13 and 41 months in our model. Some lawful entry dates sit closer than that.
This article compares two clocks. The first clock is the time to qualify a second source. The second clock is the time left before you may lawfully sell. We use FDA documents, a federal regulation, court-related settlement terms and FDA shortage records. We label every calculated number as analysis. We also give the model so that you can change the inputs.
The Short Answer
Why is the second-source qualification timeline longer than the freedom-to-operate window?
A second source needs a new API site, three batches, stability data, an FDA filing and an FDA review. In our model, the supplement route takes 18 to 37 months. A lawful entry date often sits closer than that. If you start late, you launch with one source or you launch late.
The Five Findings That Matter
Finding 1: FDA review is 6 to 10 months for a supplement
Under the GDUFA III commitment letter, FDA aims to act on 90 percent of standard original ANDAs within 10 months [1]. A standard prior approval supplement (PAS) has a goal of 6 months without a preapproval inspection and 10 months with one [1]. A priority PAS has a goal of 4 months without an inspection [1].
Finding 2: Stability data adds a 6-month clock
FDA recommends 6 months of accelerated data and 6 months of long-term data at the time of ANDA submission [2]. The two studies run at the same time. A new source therefore carries at least 6 months of stability time in our model.
Finding 3: The model range is 13 to 41 months
Analysis: the CBE-30 route takes 13 to 17 months. The PAS route takes 18 to 37 months. A new ANDA route takes 23 to 41 months. Section “Timeline Model Results” shows the stages.
Finding 4: One in five full approvals comes in the first cycle
In fiscal year 2025, FDA fully approved 689 ANDAs. Of these, 137 (19.9 percent) came in the first review cycle, according to Lachman Consultants’ summary of the FDA statistical report [3]. Plan for amendments.
Finding 5: Four of four sample entry dates fail the base PAS case
Analysis: we tested entry dates of 1 July 2027, 1 January 2028, 1 July 2028 and 1 January 2029. A company that has not started by 18 October 2026 cannot finish the base PAS case (29 months) before any of the four dates.
Definitions: Second Source, Freedom to Operate, Runway and Lead Time
What is second-source qualification?
Second-source qualification is the work needed to make a product with an API or drug product site that FDA has not yet accepted for that product. The work ends when FDA accepts the change, or when the change is allowed to go into use. In this article, the second source is mostly an API source.
What is a freedom-to-operate window?
A freedom-to-operate (FTO) window is the period in which a company may make and sell a product without infringing a patent that the owner can enforce. The window starts on a lawful date. That date can come from patent expiry, a settlement license, a court decision or the end of a regulatory stay. In the FDA process, a Paragraph IV certification states that a listed patent is “invalid, unenforceable, or will not be infringed by the generic product” [4].
What are runway and lead time?
These two terms are ours. They are not industry standards.
Runway is the number of months from today to the lawful entry date.
Lead time is the number of months needed to qualify the second source.
The gap is runway minus lead time. A negative gap means that the second source cannot be ready on the lawful date.
Is the FTO window the same as patent expiry?
No. A patent expiry date is one input. A second source can fall under a separate patent that covers its route or its solid form. IPFray reports that U.S. Patent No. 11,096,918, which covers an amorphous solid form in the Entresto dispute, expires on 9 November 2026 [5]. A supplier that uses that form would need a different lawful date than a supplier that does not.
Methodology: How We Built the Timeline Model
What data did we use?
We used these sources:
FDA’s April 2004 guidance, “Changes to an Approved NDA or ANDA” [6].
Title 21 of the Code of Federal Regulations, section 314.70 [7].
The GDUFA III commitment letter for fiscal years 2023 to 2027 [1].
FDA’s May 2014 stability questions-and-answers guidance for ANDAs [2].
FDA’s GDUFA III drug master file (DMF) page, which is current as of 22 July 2026 [8].
For cases, we used FDA recall updates, an FDA letter, an FDA report to Congress, a company press release and one secondary patent source. We did not use any non-public data.
How did we calculate the lead times?
We split the work into six stages: tech transfer (T), registration batches (B), stability (S), filing preparation (F), FDA review (R) and amendment cycles (A). We added the stage durations in months. We then subtracted each total from a hypothetical entry date with the Python library dateutil. The runway uses 18 October 2026 as the start date.
FDA sets the review goals (R and A). FDA also sets the 6-month stability data level (S). We chose T, B and F ourselves. Those are assumptions and not documented statistics.
Stage
Fast case (months)
Base case (months)
Slow case (months)
Basis
T: select supplier, tech transfer
3
5
6
Our assumption
B: three registration batches
2
3
3
Our assumption; FDA expects three batches [2]
S: stability at filing
6
6
6
FDA: 6 months accelerated and 6 months long-term, run together [2]
F: dossier preparation and filing (PAS)
1
2
2
Our assumption
F: dossier preparation and filing (ANDA)
2
3
3
Our assumption
R: review, CBE-30
1
1
not used
30-day wait in 21 CFR 314.70(c)(4) [7]
R: review, PAS
6
10
10
GDUFA III: 6 months, or 10 with inspection [1]
R: review, original ANDA
10
10
10
GDUFA III standard goal [1]
A: amendments, PAS
0
3
10
GDUFA III: 3-month minor amendment; 10-month major amendment with inspection [1]
A: amendments, ANDA
0
8
13
GDUFA III: 8-month major amendment; 10 plus 3 months [1]
What does the model leave out?
The model leaves out these items: bioequivalence studies, commercial-scale validation lots, FDA filing-review queues before the review clock starts, supplier DMF development, and launch preparation. Each item adds time. The model therefore understates the lead time for a new ANDA. It also assumes that FDA meets its goals. Goals are not guarantees.
How Long Does It Take to Qualify a Second API Source?
Stage 1: What happens during tech transfer and registration batches?
The new API maker must show that it can make material to the same specification. The drug product maker must make three drug product batches with that API. FDA expects data from three pilot-scale batches, or two pilot batches plus one small-scale batch, for the drug product [2]. The same guidance asks for formal DMF stability data on at least three primary batches of drug substance [2].
Why do we assume 5 to 8 months for this stage?
We assume 3 to 6 months for tech transfer and 2 to 3 months for batches. These are planning assumptions. Your supplier may be faster or slower. Test them against your own project history.
Stage 2: How much stability data does FDA want at filing?
FDA recommends that applicants “submit 6 months of accelerated stability data and 6 months of long-term stability data at the time of submission” [2]. If the accelerated data show a significant change, FDA recommends 6 months of intermediate data [2]. That would extend the clock. Our model does not add this case.
What happens after approval?
The guidance asks applicants to commit one batch of drug product and one batch of drug substance to the annual long-term stability program [2]. This commitment does not delay the filing. It adds a duty after approval.
Stage 3: Which filing route applies to a new API source?
The route decides the review time. A CBE-30 supplement allows distribution 30 days after FDA receives it [7]. A prior approval supplement requires approval before distribution [7]. The 2004 guidance does not use the word “supplier” [6]. It sorts changes by site, process and route.
What does 21 CFR 314.70 say?
Section 314.70(b) requires a prior approval supplement for changes with a substantial potential to affect product quality. One example is a “change in the synthesis or manufacture of the drug substance that may affect the impurity profile” [7]. Section 314.70(c) covers moderate changes. If FDA tells the holder within 30 days that prior approval is needed, the holder “must not distribute” the product made with the change [7].
What does the 2004 guidance say about sites and routes?
The guidance lists these major changes: a move to a site that has no satisfactory CGMP inspection for that operation, a “change in the route of synthesis of a drug substance,” and “any process change made after the final intermediate processing step in drug substance manufacture” [6]. It lists a site move for drug substance manufacture as moderate when no other provision applies [6].
Why will a new API source often need a PAS?
Analysis: a new API source usually means a new site. It often means a different route or a different impurity profile. Each of those facts can move the change from moderate to major. We therefore treat the PAS as the base route. We show CBE-30 only as a best case. Your regulatory team must decide the category for each product.
Stage 4: What are the FDA review goals?
The GDUFA III goals give the review part of the clock. The table below lists the goals that matter for second-source work.
Submission type
FDA goal
Source
Standard original ANDA
90 percent within 10 months
GDUFA III I(A)(1) [1]
Priority original ANDA
8 months if pre-submission facility correspondence (PFC) requirements are met; otherwise 10 months
GDUFA III I(A)(2) [1]
Standard major ANDA amendment
8 months without inspection; 10 months with inspection
GDUFA III I(A)(4) [1]
Minor ANDA amendment
3 months
GDUFA III I(A)(7) [1]
Standard PAS
6 months without inspection; 10 months with inspection
GDUFA III I(B)(1) [1]
Priority PAS
4 months without inspection; 8 or 10 months with inspection
GDUFA III I(B)(2) [1]
Standard major PAS amendment
6 months without inspection; 10 months with inspection
GDUFA III I(B)(3) [1]
Minor PAS amendment
3 months
GDUFA III I(B)(5) [1]
The letter sets no goal for CBE-30 supplements. It lists them as a workload item only [1].
Does FDA meet the PAS goals?
FDA’s fiscal year 2023 web posting reports that 99 percent of completed standard PAS actions without an inspection met the 6-month goal. It lists 839 completed actions of 1,400 in that category and says the numbers may change [9]. On-time review is not the same as approval. A PAS can still end with a deficiency letter.
The table lists the supplement rows from that posting. The posting says that counts reflect data at the time of posting and may change [9].
Category (FY 2023 posting)
Goal
Actions completed
On time
Source
Standard PAS, no inspection
6 months
839 of 1,400
99%
[9]
Standard PAS, inspection required
10 months
24 of 66
100%
[9]
Priority PAS, no inspection
4 months
63 of 97
92%
[9]
Priority PAS, inspection, no PFC status
10 months
3 of 11
100%
[9]
Standard major PAS amendment, no inspection
6 months
87 of 122
100%
[9]
Standard major PAS amendment, inspection
10 months
4 of 10
100%
[9]
Minor PAS amendments
3 months
174 of 224
97%
[9]
Does the workload leave room?
Lachman Consultants reports 1,489 PAS submissions in fiscal year 2025, up from 1,414 in fiscal year 2024 [3]. Analysis: that is an increase of 75 submissions, or 5.3 percent.
Stage 5: Can early DMF assessment shorten the clock?
Maybe. GDUFA III lets FDA start to assess Type II API DMFs “6 months prior to an ANDA or PAS submission” that references the DMF [8]. FDA has a draft guidance on the request process [8]. Our model does not credit this program. If your supplier qualifies, the program could move some review work ahead of the filing. We have no data on how much time it saves.
Timeline Model Results: 13 to 41 Months
How many months does each filing route take?
Analysis: the table adds the stage values from the methodology section. These totals are calculated figures. No source reports them as statistics.
Route
Fast case
Base case
Slow case
CBE-30 supplement (moderate change only)
13 months
17 months
falls back to PAS
Prior approval supplement
18 months
29 months
37 months
New ANDA with the new API source
23 months
35 months
41 months
The review step is 6 to 10 months in the PAS case. The other steps add 12 to 27 months. Analysis: most of the lead time sits before the filing and in the amendment cycles, and not in the base review goal.
What are the latest start dates for four sample entry dates?
Analysis: the entry dates below are hypothetical. They are not forecasts for any drug. The latest start date is the entry date minus the lead time. The runway is counted from 18 October 2026.
Hypothetical entry date
Runway (months)
CBE-30, base (17)
PAS, fast (18)
PAS, base (29)
PAS, slow (37)
New ANDA, base (35)
1 July 2027
8.4
Feb 2026 (passed)
Jan 2026 (passed)
Feb 2025 (passed)
Jun 2024 (passed)
Aug 2024 (passed)
1 January 2028
14.4
Aug 2026 (passed)
Jul 2026 (passed)
Aug 2025 (passed)
Dec 2024 (passed)
Feb 2025 (passed)
1 July 2028
20.4
Feb 2027
Jan 2027
Feb 2026 (passed)
Jun 2025 (passed)
Aug 2025 (passed)
1 January 2029
26.4
Aug 2027
Jul 2027
Aug 2026 (passed)
Dec 2025 (passed)
Feb 2026 (passed)
Analysis: the CBE-30 best case still fails for the 2027 date. The base PAS case fails for all four dates. Only the fast PAS case works for the last two dates.
How sensitive is the result to our assumptions?
We chose three of the six stage values: tech transfer, batches and filing preparation. The other three come from FDA documents. To test the effect, we set the three chosen stages to zero. This gives a floor case that depends only on FDA values.
What is the floor case?
Analysis: the floor is the stability time plus the review time plus the amendment time. It is the shortest result that our sources allow. Real projects will take longer.
Route
Floor, fast case
Floor, base case
Floor, slow case
CBE-30 supplement
7 months
7 months
not used
Prior approval supplement
12 months
19 months
26 months
New ANDA
16 months
24 months
29 months
Does the floor case change the answer?
Partly. With the three chosen stages at zero, the base PAS case still needs 19 months. That is longer than the runway for the first two sample dates (8.4 and 14.4 months). The base PAS floor fits the 1 July 2028 date (20.4 months). The slow PAS floor of 26 months just fits the 1 January 2029 date (26.4 months). Our result does not depend only on our own assumptions. FDA’s goals and the 6-month stability clock set a large part of it.
What are the runway classes?
This is an original framework. It is not an industry classification. We classify the runway against the PAS lead times of 18, 29 and 37 months.
Class
Runway versus PAS lead time
Meaning
Sample dates in this article
A
37 months or more
The slow case fits.
none
B
29 to under 37 months
The base case fits. The slow case does not.
none
C
18 to under 29 months
Only the fast case fits.
1 July 2028; 1 January 2029
D
Under 18 months
No PAS case fits. Plan to launch with one source.
1 July 2027; 1 January 2028
Where Does the Freedom-to-Operate Window Come From?
Patent expiry and pediatric exclusivity
IPFray reports that U.S. Patent No. 8,101,659 in the Entresto dispute ran to 15 July 2025 after pediatric exclusivity [5]. The same source reports that the Delaware court ordered FDA to set MSN’s approval date to “no earlier than July 16, 2025” in April 2025 [5]. IPFray is a secondary source. Check the court order before you rely on the dates.
Settlement-licensed entry
A settlement can set the lawful date. Bristol Myers Squibb announced that Dr. Reddy’s may sell unlimited generic lenalidomide “no earlier than January 31, 2026” [10]. The release says the volume-limited license begins “after the March 2022 date previously granted to Natco” [10].
What is the 30-month stay and how does it end?
When a brand sponsor sues within 45 days of the ANDA notice, FDA approval is “generally postponed for 30 months” [4]. FDA says the postponement ends at 30 months “unless the patent expires or is judged to be invalid or not infringed before that time” [4]. A court ruling can therefore open the window early. The date is hard to predict. A plan that needs 29 months of lead time cannot wait for the ruling.
Can the second source have its own patent problem?
Yes. The entry date for the drug may be clear while the supplier’s route or form is not. The ‘918 patent in the Entresto dispute covers an amorphous solid form and expires on 9 November 2026, according to IPFray [5]. Analysis: a second source that makes a different solid form may avoid a form patent. A different form can also change the impurity profile and the filing route.
Why 180-Day Exclusivity Adds a Second Deadline for First Filers
What is the 30-month tentative approval rule?
The statute lists a forfeiture event for a first applicant that “fails to obtain tentative approval of the application within 30 months after the date on which the application is filed” [11]. FDA quoted this text in a 2009 letter on nateglinide tablets. In that letter, FDA found that at least one applicant forfeited exclusivity on this ground [11].
How many ANDAs clear review in the first cycle?
Fiscal year 2025: 137 of 689 fully approved ANDAs (19.9 percent) were approved in the first review cycle. Source: Lachman Consultants, summary of the FDA Office of Generic Drugs statistical report [3].
The same summary reports 250 tentative approvals in fiscal year 2025. Of these, 49 (19.6 percent) came in the first cycle [3]. Analysis: about four of five approvals needed at least one more cycle.
Cycle arithmetic: how much margin does the 30-month clock leave?
Analysis: an original ANDA review is 10 months [1]. A standard major amendment adds 8 to 10 months [1]. Together, that is 18 to 20 months. The margin to the 30-month limit is then 10 to 12 months.
Now add a mid-review API source change. That change is a major amendment. It adds 8 to 10 months [1]. The margin falls to between 0 and 4 months. A third cycle would leave no margin.
What does this mean for the first filer?
A first filer should qualify its API source before submission. A source change during review uses most of the tentative approval margin. We do not know how each past applicant handled this. Public data on source changes during review are limited.
Case Study: Valsartan, July 2018
What did FDA say about the valsartan API source?
On 18 July 2018, FDA listed recalls by Teva (labeled Major Pharmaceuticals and Actavis) and Prinston (labeled Solco Healthcare) [12]. FDA attributed the N-nitrosodimethylamine (NDMA) to active substance made by Zhejiang Huahai Pharmaceuticals in Linhai, China [12]. FDA said “the agency believes the NDMA is related to changes in the way the active substance was manufactured” [12].
How far did the recall spread?
FDA said some levels of the impurity “may have been in the valsartan-containing products for as long as four years” [12]. By 27 July 2018, FDA listed nine repackagers: three that had recalled Teva or Prinston products and six that had recalled or were expected to recall [12]. The nine repackagers are the count from FDA’s list. They are not a count of all affected labelers.
What does valsartan show about second sources?
Analysis: one API process change reached several labels. A second source could limit that exposure only if it had been qualified before the event. Our fast PAS case needs 18 months. A buyer that starts after a recall waits through that time. FDA’s July entries do not discuss shortages, so we draw no shortage conclusion from them [12].
Is a process change at the supplier a filing event?
For an applicant, a change in synthesis that “may affect the impurity profile” falls under the prior approval category in 21 CFR 314.70(b) [7]. FDA’s statement links the NDMA to a manufacturing change. We do not know which filings the supplier made. We make no claim about that.
Case Study: Cisplatin Temporary Importation, December 2023
What did FDA allow?
In a letter dated 6 December 2023, Qilu Pharmaceutical began a temporary import of cisplatin injection (50 mg/50 mL) with Chinese-only labeling. Apotex distributed it in the United States [13]. The letter says the product “is marketed and manufactured in China and is not FDA-approved” [13]. It cites the “critical shortage of CISplatin Injection in the United States” [13].
How long was the temporary supply meant to last?
The letter lists 12 lots with expiry dates from 26 September 2025 to 11 October 2025 [13]. The lots are time-limited. Analysis: this is a stopgap. It does not replace a qualified second source. A commercial plan cannot count on a similar FDA action.
Case Study: Revlimid Volume-Limited Licenses
How did the settlement stage the window?
The Dr. Reddy’s settlement gave two dates. A volume-limited license started after the March 2022 Natco date. An unlimited license started no earlier than 31 January 2026 [10]. The release does not give the exact start date or the volume limits [10].
What does staging mean for supply?
Analysis: from 1 March 2022 to 31 January 2026 is about 47 months. The volume-limited license began after March 2022, so the volume-limited period was at most about 47 months. During that time, a licensee has a volume cap. A supply plan can use that time to qualify more capacity before the cap lifts. A licensee that waits for the unlimited date has the same 13 to 41 month lead time as any other applicant.
Case Study: Entresto Dates in 2025 and 2026
What are the reported dates?
IPFray reports three dates [5]:
15 July 2025, the end of the ‘659 patent term with pediatric exclusivity.
16 July 2025, the earliest approval date the Delaware court ordered in April 2025.
9 November 2026, the expiry of the ‘918 amorphous solid form patent.
The source is secondary and, in our reading, unclear about which patent a June 2025 settlement covered. We do not rely on the settlement. We use only the patent dates.
What does a 22-day runway mean?
Analysis: from 18 October 2026 to 9 November 2026 is 22 days. No second API source can be qualified in 22 days. The date is useful only as a test. A form patent can end soon after a drug launches, and a supplier’s path can be separate from the drug’s path. Check each patent that touches your supplier.
Case Comparison Table: Four Events and the Clock Each One Tested
What do the four cases have in common?
Each case shows a fixed date or a sudden failure. In each case, the supply plan had to meet that event. The table lists the documented facts. The last column is our analysis.
Event
Date
Documented fact
Clock tested (analysis)
Source
Valsartan recalls
July 2018
FDA tied NDMA to API from one maker; recalls by Teva and Prinston labels; nine repackagers listed by 27 July
Qualification time after a failure
[12]
Cisplatin temporary import
6 December 2023
Qilu product imported, distributed by Apotex; not FDA-approved; 12 lots
Approved supply was short
[13]
Revlimid settlement (Dr. Reddy’s)
17 September 2020
Volume-limited license after March 2022; unlimited license no earlier than 31 January 2026
Staged lawful dates
[10]
Entresto patents
2025 to 2026
‘659 term to 15 July 2025; approval no earlier than 16 July 2025; ‘918 expires 9 November 2026
Separate dates for drug and form
[5]
What Does the Shortage Record Show?
How many shortages did FDA record in 2023?
FDA’s calendar year 2023 report to Congress counts 55 new shortages: 33 at CDER and 22 at CBER [14]. It counts 98 ongoing shortages on 31 December 2023: 94 at CDER and 4 at CBER [14]. The report says “more than half of the shortages seen in CY 2023 were due, in part, to increases in demand” [14].
What are the root causes FDA named in 2019?
FDA’s 2019 report names three root causes: weak incentives to make low-profit drugs, a market that does not reward “mature quality systems,” and logistical and regulatory barriers to recovery [15]. For shortages from 2013 to 2017, FDA reports that 42 percent had a significant production increase and 30 percent had full supply restored to pre-shortage levels [15]. The report was published in October 2019 and updated in February 2020 [15].
How does this relate to the timeline gap?
Analysis: demand rises and site failures give little warning. A second source takes 13 to 41 months in our model. A buyer cannot qualify a source after a shortage starts and expect supply in the same quarter.
What This Means for Generic Manufacturers
When should you start second-source work?
Start when you have a credible entry date, not when you have a court decision. Use the latest start date formula in this article. If the date has passed, move to a mitigation plan.
How can you shorten the clock?
The sources suggest four levers. Each lever is analysis, not a promise.
Choose a supplier whose site has a satisfactory CGMP inspection for the operation. A move to a site without one is a major change [6].
Keep the approved synthesis route. A route change is a major change [6].
Ask for early DMF assessment, if the supplier is eligible [8].
Run stability for 6 months before you file, and not after [2].
What This Means for Brand Manufacturers
Why does a brand need a second source before loss of exclusivity?
A brand that holds an NDA reports manufacturing changes under the same rule [7]. The same lead times apply. Analysis: volume can rise or fall quickly near loss of exclusivity, and a single API source limits the response. A brand should compare its own entry-risk dates with the same lead times.
What about buyers, medical affairs and pharmacovigilance teams?
Buyers can ask suppliers which API sources sit behind each product. Pharmacovigilance teams can plan impurity monitoring for any source change. The valsartan recalls show why [12]. These two actions need no FDA clock.
How to Use DrugPatentWatch in This Analysis
What can DrugPatentWatch supply?
DrugPatentWatch says it draws on the FDA Orange Book, ANDA filings, litigation records and patent registers. It also lists coverage of 134 countries and access to full complaints and court documents [16]. Those inputs help you set the entry date and the runway.
What can it not supply?
Its home page does not list supplier or DMF data [16]. Use the FDA record, the supplier and your own regulatory file for those. Use the court order or settlement text for the final lawful date. A database is a starting point for that work.
What Happens If the Window Closes First?
Scenario 1: Launch with one source
You launch on the lawful date with the approved source. You keep the second source in progress. The risk is a recall or site failure, as in the valsartan case [12]. Write that risk into the supply plan.
Scenario 2: Delay the launch
You wait until the second source is approved. This avoids single-source risk. It gives up sales in the window. In a market with a 180-day exclusivity period, a late tentative approval can trigger the forfeiture event and cost the exclusivity period [11].
Scenario 3: Use a CBE-30 only if the change qualifies
This is the best case at 13 to 17 months. It holds only if FDA does not require prior approval within 30 days [7]. If FDA does require it, the product made with the change cannot be distributed [7].
Key Takeaways
FDA’s GDUFA III goals are 6 months for a standard PAS without inspection, 10 months with inspection and 10 months for a standard original ANDA [1].
FDA recommends 6 months of accelerated and 6 months of long-term stability data at ANDA submission [2].
Our model gives 13 to 17 months for a CBE-30 route, 18 to 37 months for a PAS route and 23 to 41 months for a new ANDA route. These are calculated figures.
With tech transfer, batches and filing set to zero, the base PAS case still needs 19 months. That is a calculated floor.
In fiscal year 2025, 19.9 percent of full ANDA approvals came in the first cycle [3].
A first applicant that fails to get tentative approval within 30 months of filing risks forfeiture of 180-day exclusivity [11].
The base PAS case does not fit any of our four sample entry dates from July 2027 to January 2029, if work starts after 18 October 2026.
FDA used a temporary import for cisplatin in December 2023 because of a critical U.S. shortage [13].
FAQ
How long does it take to qualify a second API source for a U.S. generic?
In our model, it takes 18 to 37 months by the PAS route and 23 to 41 months by a new ANDA. These are calculated figures that rest on FDA review goals [1] and our stage assumptions.
Can I sell 30 days after I file a CBE-30 supplement?
Only if FDA does not say within 30 days that prior approval is needed or that information is missing [7].
What stability data does FDA want for a new ANDA?
FDA recommends data from three pilot-scale batches, with 6 months of accelerated data and 6 months of long-term data at submission [2].
How long does FDA take to review a prior approval supplement?
The GDUFA III goal is 6 months for a standard PAS without an inspection. It is 10 months with an inspection [1].
What happens to 180-day exclusivity if tentative approval is late?
A first applicant that does not get tentative approval within 30 months after filing faces a statutory forfeiture event [11].
How does the 30-month stay end?
It ends at 30 months. It can end earlier if the patent expires or a court finds it invalid or not infringed [4].
Can FDA assess the API DMF before I file?
GDUFA III allows an early assessment of Type II API DMFs starting 6 months before an ANDA or PAS that references the DMF [8].
Why do shortages last after a supply failure?
FDA names weak incentives, a market that does not reward quality systems and recovery barriers [15]. For shortages from 2013 to 2017, 30 percent had full supply restored [15].
What did the valsartan recalls show about single-source API?
FDA tied the NDMA to API from one maker and listed recalls from several labelers and nine repackagers within two weeks of the first notice [12].
When could Dr. Reddy’s sell unlimited generic lenalidomide in the United States?
Under the settlement, no earlier than 31 January 2026 [10].
References
U.S. Food and Drug Administration. (n.d.). GDUFA III commitment letter: Performance goals and program enhancements, fiscal years 2023-2027. https://fda.gov/media/153631/download
U.S. Food and Drug Administration. (2014, May). ANDAs: Stability testing of drug substances and products, questions and answers: Guidance for industry. https://www.hhs.gov/guidance/sites/default/files/hhs-guidance-documents/FDA/ANDAs–Stability-Testing-of-Drug-Substances-and-Products–Questions-and-Answers.pdf
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