Our next company is Amphastar Pharmaceuticals, and with me is President Jason Shandell. My name is Ashwani Verma. I'm with the U.S. Major and Specialty Pharmaceuticals team with Bank of America. And Jason, just over to you, and let's take a look at the slides.
Great, great. Thank you. So I'll just get the light. Okay, there we go. So I'm just going to go through the slides. I know we only have a short amount of time, and then can open it up for some quick Q&A. And so let's go through the forward-looking statements. So essentially, Amphastar, we're headquartered in Rancho Cucamonga. That's east of downtown LA, about one hour. We're very well known for enoxaparin. It's still one of our largest revenue products. We were approved in 2011. We've always been proud of that approval. It really is a testament to our scientific capabilities with characterization and immunogenicity. And here you'll see our historical net revenues, typical of a generic company. But you'll see we went public in 2014. We were doing $210 million. For 2018, we did $295 million.
We've had some good approvals over the last couple of years that should continue that growth. We have a very deep pipeline. A lot of it's focused on complex generics, biosimilar products, namely insulin. We're working on three insulin products. Then we have some proprietary candidates that I can discuss. One of the unique attributes of Amphastar, given our size, is our vertical integration. We really pride ourselves on doing everything from research and development all the way to distribution. We have two facilities that are outside the country. One we acquired from Merck. It's Amphastar France Pharmaceuticals. They do insulin API. That's part of our vertical integration, excuse me, to get into the insulin market. Our facility in China really is going to be a big driver of our growth in the future.
They're providing many APIs to us exclusively. And also we are going to get into finished product in the China market. So now just for a quick overview of sort of one of our objectives as a company, we focus on very difficult-to-do products like an enoxaparin, like an interchangeable insulin. Areas where we believe that there's either high technical barriers to approval, or difficult manufacturing process, or difficult to secure the API. And in many instances, if we cannot procure the API, we have very sophisticated synthetic capabilities that allow us to still show sameness as a synthetic to the RLD. So as I briefly talked about enoxaparin, although that approval is now almost eight years ago, we like to keep it on the slide as a highlight of our strengths as a company.
These strengths are not just the cutting-edge technology of the characterization, the immunogenicity, but it's also our regulatory capabilities, our legal capabilities. Again, it does highlight our structure for vertical integration. It really was back in 2009 when we started our China facility that we started working on heparin to do vertical integration for enoxaparin. We like to look at ourselves as not your typical generic company. We really are a specialty pharma, and we put a lot of our money into R&D. You'll see that over the past five years, it has ranged between 14% and 20% of revenues. This really demonstrates our commitment to the pipeline. We think this is going to generate a great return on investment. We try to balance it because we do want to remain profitable going forward on an annual basis.
And so in that regard, as our revenues increase from our recent approvals, we will balance that against our R&D needs. But when we report our financials, we could be much more profitable if we chose to not reinvest that into R&D. But I think when investors see how much we're putting into R&D, it really is a testament of our future. And some of our recent approvals, I think, add to that credibility. So in terms of the generic pipeline, that's where we have currently four ANDAs on file, and that has sales of approximately $800 million based on IQVIA data. We also have five injectable ANDAs in development targeting a market of $4 billion, and six inhalation ANDAs targeting a market of $10 billion. And this slide discusses the technology platforms that are required to get approval of these sort of products.
As you'll see, characterization, that's a key attribute of Amphastar. So for all the products, it requires that. We also focus on immunogenicity, particle engineering, sustained release, and peptide and protein technology. Then in terms of the biosimilar, we are targeting insulin, three different insulin products. Just recently, we filed a pre-IND on one of the insulin products. It really is an exciting time for that market and for biosimilars in general. Recently, just a few days ago, the FDA came out with its final guidance, which discusses interchangeability, which we've always thought would be important for a product like insulin as opposed to a biosimilar where you still need a sales and marketing force. We think that our analytical tools can go to the level that will get the agency comfortable with an interchangeable insulin.
And so that's been our focus, and we'll continue those discussions. The law has it switching over to a BLA in March of 2020. And so that really is going to be our timeline. We're going to look to file a BLA after that timeframe. And currently, we're working towards that goal. And so the three insulin products that we are working on target a market of over $14 billion. And then we have four proprietary product candidates. One is the intranasal naloxone. We received a CRL in 2017, and we've been working with the agency on a variety of issues. Most namely, we're working on improving our device, and we're targeting early 2020 to file a resubmission in response to this CRL.
We also have three other projects that are at this point not disclosed, but as we work through our clinicals, we expect perhaps around phase two, if the data looks good, we can talk more about these projects. Naloxone, it remains a good opportunity for us. Our injectable product is very stable. This is just a slide that demonstrates how the crisis in the country is really not getting any better. It's unfortunate, but we are happy to be part of the solution and saving lives every day. Primatene Mist, it's a very exciting part of the story, a long saga. The history of it is on this slide. Really, in a nutshell, we were a contract manufacturer, Armstrong Pharmaceuticals, which we acquired. We contract manufactured Primatene Mist for Wyeth. We also made the EpiMist, which was the generic Primatene Mist.
We read an article in 2006 that Wyeth was not able to reformulate the CFC version into the new HFA version. So we approached them. We purchased the product in 2008. We were confident we could reformulate. The whole reason the product went away was because of the CFC, which was an environmental issue for the ozone. We successfully reformulated the product using HFA. And so it's an improved product, has a dose indicator, higher delivery efficiency, aluminum instead of glass container. And the previous peak sales were $65 million in 2010. We believe in two to three years, we can get back to those peak sales. And so just in terms of a marketing update for Primatene, we were able to launch within six weeks from our approval date. So we launched in December of 2018. It's available nationwide, currently at Walgreens, CVS, and Rite Aid.
We're in discussions right now to get it into the stores at Walmart. So far, we've had very positive consumer feedback, and also the sales trend is looking good. We get weekly information at the retail level, and we've seen the sales increase every week except for one, so it's a good trend, and we will begin a TV advertising campaign in July, which we think will really increase awareness of the product and hopefully give a good return on investment on those commercials, and then our base business remains very strong. This is a list of our key products. We produce over 20 injectable products. Many of them are critical care drugs, often on drug shortage lists, and so this business has really sustained and is a good driver of growth.
In terms of a launch update, we have had lots of approvals and launches over the last two years, and so this shows you that we did neostigmine. We launched that in November of 2017. The generic Depo-Provera, we launched in the first quarter of 2018. Isoproterenol in the middle of 2018, and then, of course, Primatene Mist at the end of 2018. We did get approval in March of enoxaparin vials, and we're planning to launch that for the full enoxaparin offering by August, and then we're still planning. We've done a small acquisition a few years ago of some IMS UK products, and we're working on increasing the capacity in our California facility, and we'll hope to launch that this year. Amphastar Nanjing Pharmaceuticals, that's our China facility. I talked about that earlier for vertical integration.
There has been a change in strategy after discussions with the Chinese government and the growing middle class in China, in balance with the quality of pharmaceutical products that are currently available. We think there's a great opportunity to sell finished product in China. And so we raised money through a private investment, $57 million. We're going to use that to create finished product lines for sale in China. We think this could be a great opportunity for the company. So just financial overview, you'll see from 2014 to 2018, we've grown revenues from 210 to 295, and our gross profit has doubled from 2014 to 2018. So it's just a snapshot of our financial statements. And this is actually one of my favorite slides, which we can end on as I see the time is running out. But you'll see the diversification of our business.
It really doesn't show the full picture because when we went public in 2014, over 50% of our revenues were enoxaparin. Now, in 2018, you can see a well-diversified portfolio. And clearly, adding in Primatene and some of the other launches will even make it more diversified when we show the 2019 pie chart. So that wraps up the presentation and leaves us just about a minute for a question.
So just quickly on the Primatene Mist launch, you're expecting to reach $65 million in two to three years. Help us understand what the sales trajectory might look like.
What is the sales trajectory?
Might look like, yeah.
Yeah. Bill, do you want to answer that one?
Yeah, sure. So we did a little over $2.59, $2.79 the first quarter of this year. And as Jason mentioned earlier, we've seen the sales grow almost every single week since we've launched the product. So it's growing nicely. Once we get the product back into Walmart, which should be later this year, it should be a big boost for us because that was over 35% of the sales previously. Initially, we set it up so that our TV advertising campaign would be beginning in the second half of the year, and we think that.
Thanks so much.
Great. Thank you.
Great having you there.
Appreciate it.
Yeah. Thanks.