Okay, well, I'm just gonna jump in and introduce our speaker, Dean Schorno, who is the CFO of Rigel Pharmaceuticals.
Thank you, Arabella, and thank you, H.C. Wainwright, for having us to your conference this year, and in particular, for all of you, for your interest in Rigel. One second. All right. We're all set. Again, thank you for your interest in Rigel. As I get started today, I'll be making some forward-looking statements, so I'd encourage you to look at our Rigel.com investor site, in particular, our SEC filings, for more information about the company. I'd also encourage you to take a look at our corporate presentation deck. I'll be moving fairly quickly through information here, and a lot more information in that deck.
Really some great, great recent news for Rigel that I'll be reviewing today. One of the main pieces of new news is we acquired the rights to Gavreto. We made the product available right at the end of June of this year, and I'll be describing that. That's an important commercial event for the company, and we're excited to have this now as a commercial product offering. The brief overview of the business is we're a hematology/oncology business. We now have three commercial products. We have Tavalisse, which was an internally developed product for chronic ITP, and that we launched in two thousand and eighteen. About twenty months ago, we in-licensed Rezlidhia, which is for IDH1 positive relapsed refractory AML.
And then most recently, as I said, we acquired the U.S. rights to Gavreto, and that's for RET fusion-positive metastatic lung cancer, non-small cell lung cancer, as well as advanced thyroid cancer. So that group of commercial assets, I'll describe, really puts a great foundation for our net revenues, both from a U.S. perspective and a global perspective. I'll also describe our development and expansion opportunities. We have great collaborations with both MD Anderson and a group called CONNECT to explore opportunities for IDH1-positive mutant cancers, not only in AML, where we're indicated for relapse refractory, but also for MDS, as well as glioma.
We're also in the process of, you know, wrapping up a dose range finding program in R289 or IRAK1/4 inhibitor program, and we're doing that work in lower risk MDS. And then finally, from an in-licensing and product acquisition perspective, as I described, there continues to be opportunities like we saw with Rezlidhia, like I'll describe with Gavreto, for us to grow our commercial capabilities. We're uniquely positioned as a company in that we have 48 field sales representatives who are calling on community doctors, the vast majority of ITP doctors in the community, but a good portion of the non-small cell lung cancer, as well as AML doctors, are also in the community.
And then we've got a specialized field sales force of nine people who are calling on the academic centers, the leukemia treatment centers, as well as the lung cancer treatment centers. So that commercial organization, coupled with our patient access programs and our reimbursement capabilities, as well as our marketing in combination with our MSL team, really provides an opportunity for us to reach these physicians and these patients in all of these disease states and really differentiates our company on the. And so that's, you know, we'll continue to look at those in-licensing and product acquisition opportunities for those reasons. From a financial discipline perspective, at the end of Q2, we reported a $1 million loss on a GAAP basis. We had about $3 million of non-cash charges, stock comp, depreciation, amortization.
So we're right at that financial break-even point. We've really executed nicely with financial discipline, and we find ourselves in a really strong cash position at this point in time and financial position. As we look at product sales, net product sales, $33.5 million in Q2, and what I'll review is the demand volume, the bottles shipped to patients and clinics, really the key drivers. You see some variation in net revenues. That's as a result of inventory fluctuation into our channel. Tavalisse, as I said, is indicated for adults with chronic ITP who have had an insufficient response to a previous therapy. That's almost always steroids. From a market opportunity perspective, there's about 81,000 patients with chronic ITP.
At any given time, about 37,000 are being watched. Their disease is in a stable state. About 20,000 are on steroids, often high-dose steroids, which isn't a sustainable therapy, and then about 24,000 are in the later line, second through fifth line. We've presented previously that we've made nice strides with that 48-person field force that I described in moving up in therapy into that second and third line where we see more patients, and these patients are typically earlier in their chronic disease journey, and therefore the response rates are better, and then the durability of response is quite strong, so making great progress in ITP.
From a growth perspective, 18% year-over-year growth in that key metric, really the bottles shipped to patients and clinics, and 8% sequential growth. You're seeing continued growth in the market, which is really a foundation to our business. $26.4 million of the net product sales that I'd previously described are from Tavalisse. So still the majority of our net product sales. Rezlidhia's indicated in IDH1 positive relapse refractory AML. From a market opportunity, from a medical need perspective, there's about 20,000 patients in the US with AML. Unfortunately, about half of those patients, a bit more than half of those patients will succumb to their disease. And 6%-9% of the patients are IDH1 positive, and that's really the target opportunity for us.
Once the relapse refractory population's identified in these orange boxes, there's about 1,000 patients, so significant opportunity for those patients and for Rigel. From a sales performance perspective, you see on the left, we have continued growth in the patient bottles shipped to patients and clinics, our demand volume, and, you know, significant revenue contribution now of $5 million, but again, growing as we continue to enter this market. Some news that we announced just last week was an expansion of our collaboration with Kissei in Japan. So Kissei now has the Japanese, Korea, and Taiwan rights for Rezlidhia. From a Tavalisse perspective, we currently have a relationship with Kissei, who have product available in Japan. We also have collaborations with Grifols.
Again, this is for ITP, and we have collaborations with Grifols as well as Medison globally, and we'd look to expand the international capabilities with respect to Rezlidhia also, and we're really excited to have Kissei continue to work with us there. The economics, we had a $10 million upfront associated with that effort. I'd encourage you to look at our press release from a week ago and the 8-K for more details there. From a Gavreto perspective, as I described, we acquired the US rights to Gavreto back in February. In June, late June, the last few days, we made the product available, and the product's indicated for RET fusion positive metastatic non-small cell lung cancer, as well as advanced thyroid cancer.
From a non-small cell lung cancer opportunity, the RET fusion-positive subset of patients is well identified. We get great leverage across the organization I described. So from a distribution perspective, a patient access and reimbursement perspective, very, very strong capabilities there, and very complementary to the field sales force I described. So about half of the patients are seen in the community setting, so that 48-person field sales force handles that. And then the specialty. We call them IBMs, Institutional Business Managers, are calling on the academic centers. What we're seeing is, and what we'd expect for both Rezlidhia and Gavreto is, you know, we're seeing that the KOLs, you know, get used to the product, and then you see utilization in the community center.
On the right side, you see really the distribution of the market. About 25% of these RET fusion positive patients are currently getting MKIs, and chemotherapy, plus, checkpoint inhibitors. That's really a suboptimal treatment paradigm. So we believe that there's possibility for growth there. And you see down below that, the Gavreto product has about 15% of the market, and the competitive product has about 60%, so there's opportunity for us there, too. The plan for the current quarter is really the third quarter that we're in, is to transition the patients who were previously on the Genentech-labeled drug to the Rigel-labeled Gavreto, and then we'll work on those expansion opportunities into the future.
Pralsetinib, Gavreto, it's once daily oral, high durable response rates, and an inventory stocking order. We had $1.9 million of net product sales in the second quarter. That's really just an inventory stocking order. In Genentech's hands, they reported $28 million in net revenues for 2023 full year. Clinical development programs, you know, really exciting opportunities for the business. Olutasidenib, I'll describe an MD Anderson and CONNECT collaboration, where we're looking at IDH1 mutant cancers in AML, MDS, and glioma. We'll go through the R289 program in lower risk MDS. And in fostamatinib, we continue to have a variety of ISTs that we're supporting, and we'll continue to do so. On the right side, we continue to be looking for the differentiated assets-...
like Rezlidhia, like Gavreto, in hematology, oncology, and related areas, and really late-stage assets that are either, you know, registrational or could be launched, as we saw in Gavreto. From the MD Anderson Alliance, we announced last week that the first patient was dosed in the first of what will be four, could be more studies. That study is looking at a combination of venetoclax, decitabine, both infused and oral, as well as olutasidenib. We'll be looking at newly diagnosed patients as well as relapsed refractory patients. Excited to have that program initiated. We plan to do incremental programs with MD Anderson, including higher-risk MDS, and that's in combination therapy, and then monotherapy in lower risk MDS as well as CCUS, as well as post-transplant maintenance.
The relationship with MD Anderson is a great one. From an efficiency perspective, the ability to launch these studies to enroll patients, as MD Anderson has a broad range of patients, and to in these open label trials see data is really important to us. The economics are also very good. We have $15 million arrangement with MD Anderson over a five-year period. So really a great way for us to for Rigel to determine how to best enter these additional opportunities in with IDH1-positive disease with Rezlidhia. Similar to MD Anderson, we're also have a relationship with CONNECT, which has a broader trial ongoing, and we'll be looking at patients with high-grade glioma. And again, another important opportunity.
Both Forma and others in the industry have done research into MDS, a variety of AML opportunities, as well as glioma, and IDH1 susceptible disease is important, so we're excited to look at this population. Again, open label trial from an efficiency perspective, the trial's already established. We can slot right into it, so it's very time efficient and also economically quite efficient, with $3 million over four years. From an IRAK1/4 perspective, our R289 program, what we've seen in both preclinical as well as, you know, some clinical work we've done, is that IRAK1/4. Our data shows that it's more suppressive of a broad range of cytokines than IRAK4 alone, some of the competing opportunities.
We've also seen in an LPS challenge in our first in-human studies, that we've administered LPS, and then we saw a broad range of cytokine suppression. All of that gave us confidence to move into a lower risk MDS study, where we're in the dose escalation phase. We recently completed the dose level for the 250 milligram BID dosing, and we're moving into Dose Level Five. What we look to see in this study, before we move to the dose expansion phase on the right of that graphic, is we'll look for, first of all, for safety. Then secondary endpoints include transfusion independence, response rates, PK/PD.
We look to see preliminary data on this work here towards the end of 2024. We expect to present data at ASH. We also have the RIPK1 program internally developed by Rigel. So Rigel developed this our SYK program, which was the foundation of fostamatinib, Tavalisse, the IRAK1/4 program we talked about, as well as this RIPK1 program, which we have a collaboration agreement with our partner, Lilly, in both immune diseases as well as CNS diseases. Lilly is forwarding the systemic disease opportunities with a phase IIa in rheumatoid arthritis, and they'll look to present preliminary data, which will be made available to us, you know, in the first half of 2025.
Excited about this partnership, and Lilly is the ideal partner to move forward into the broad range of possibilities for R289. They also have from us a basket of potential molecules for CNS-penetrant disease. So we'll look to see that move forward into the future. From a financial perspective, we've talked about the nice growth in revenues. There's the nice collaboration revenues. In the lower left here, you see that as of March thirty-first, we had $49.6 million. You know, three months later, we're still at $49.1 million. So we're, you know, from a cash flow perspective, from a financial discipline perspective, quite strong. What's the future hold?
Continuing to grow the commercial franchise that we have across Tavalisse, Rezlidhia-