Category Archives: Johnson & Johnson

Brodalumab for Psoriasis – what a mess

Let’s agree that the headline “Suicide Stunner” – penned by John Carroll for FierceBiotech – can never auger anything but very bad news, and never more so then when it is used to describe clinical trial results. Released on the Friday before the long US holiday weekend, bookended to the announcement of positive news on it’s PSCK9 program, Amgen stated that it was walking away from an expensive co-development program with AstraZeneca, basically washing it’s hands of the anti-IL-17 receptor (IL-17R) antibody brodalumab because of suicidal tendencies and actual suicides that occurred in the Phase 3 psoriasis trials. Brodalumab is under development for the treatment of plaque psoriasis, psoriatic arthritis and axial spondyloarthritis. Amgen stated that they believed that the approval label for brodalumab would contain warning language regarding suicide risk, and this would limit the success of the drug. By using such language while pulling the plug Amgen has essentially put AstraZeneca in the position of having to prove to the FDA that there is no suicide risk.

Holy crap.

Note here that we are not talking about a psychiatric drug, where the risk of suicide might be the consequence of trying to re-align an aberrant central nervous system. Instead we are talking about a drug that targets autoimmune disorders by blocking the action of T cells. This is not a biology linked to psychiatric health, at least not as we understand it today (more on this later).

Backing up: in April 2012, AstraZeneca and Amgen announced a collaboration to jointly develop and commercialize five clinical-stage monoclonal antibodies from Amgen’s inflammation portfolio: AMG 139, AMG 157, AMG 181, AMG 557 and brodalumab (aka AMG 827). The drivers for the collaboration were Amgen’s biologics expertise, the strong respiratory, inflammation and asthma development expertise of MedImmune (AstraZeneca’s biologics division), AstraZeneca’s global commercial reach in respiratory and gastrointestinal diseases, and the shared resources of two experienced R&D organizations

Under the terms of the agreement, AstraZeneca paid Amgen a $50MM upfront payment and the companies shared development costs. The breakout was as follows: AstraZeneca was responsible for approximately 65 percent of costs for the 2012-2014 period, and the companies now split costs equally. Amgen was to book sales globally and retain a low single-digit royalty for brodalumab. Amgen retained a mid single-digit royalty for the rest of the portfolio with remaining profits to be shared equally between the partners.

It gets even more complicated. Amgen was to lead the development and commercialization of brodalumab (and AMG 557, see below). Amgen was to assume promotion responsibility for brodalumab in dermatology indications in North America, and in rheumatology in North America and Europe. AstraZeneca was to assume promotion responsibility in respiratory and dermatology indications ex-North America. AstraZeneca remains responsible for leading the development and commercialization of AMG 139, AMG 157 and AMG 181. We’ll touch on these other antibodies at the very end.

Back to brodalumab. On balance, Amgen was on the hook for the development and commercialization costs, direct, indirect and ongoing, for dermatology indications in the US and also rheumatology, which in this case refers to psoriatic arthritis and axial spondyloarthritis. On the other hand, AstraZeneca was on the hook for commercialization in respiratory indications worldwide, and dermatology ex-US. This is interesting because brodalumab failed in its’ respiratory indication, moderate to severe asthma, and failed late, in a Phase 2b patient subset trial. So, on balance, much of the overall development cost seems to have shifted back onto Amgen over time (this is not to say that the companies would not have changed terms mid-term, they may have).

Two weeks ago I chaired a session on “Biologics for Autoimmune Disease” at the PEGS conference on Boston. In my opening remarks I used psoriasis as an example of an indication in which we were making clear and important progress, including with IL-17-directed therapeutics. Indeed, psoriasis is now a “crowded” indication commercially, with antibodies and receptor fusion proteins targeting the TNFs, IL-6, IL-12, IL-17, and IL-23 pathways all showing at least some activity. Notably, IL-17 and IL-23 targeting drugs appear to offer the greatest benefit in clearing psoriatic plaques. These pathways intersect in myriad ways, not all of which are well understood. This cartoon shows the effector cytokines and the receptors are expressed by diverse cell types, including dendritic cells, macrophages, T cells, and keratinocytes in the dermis.

IL-17 and friends

In simplistic terms, IL-6 triggers IL-12 and IL-23, and IL-23 triggers IL-17. As mentioned, the IL-17 and IL-23 targeting agents have great efficacy in psoriasis. Amgen and AstraZeneca were preparing an NDA (new drug application) for FDA submission based on results from three large Phase 3 studies. Here are the listed Phase 3 programs for brodalumab:

broda 1

I suppose those Phase 3 studies in psoriatic arthritis will now be tabled or transferred to AstraZeneca. For the sake of completeness here are the earlier studies:

broda 2

Certainly the clinical program was a robust one. So, what went wrong? Amgen R&D head Sean Harper summed up Amgen’s thinking about the suicide issue in the press release: “During our preparation process for regulatory submissions, we came to believe that labeling requirements likely would limit the appropriate patient population for brodalumab.”

The news aggregator and commentary website UpdatesPlus had this to add, questioning whether this result was “bad luck, bad target or victim of brodalumab’s efficacy: Despite high efficacy in Phase 3 studies, whispers of suicidality associated with brodalumab started to emerge at AAD.  At the time Amgen suggested this was related to disease however the company refused to comment on total rates and whether events were seen across arms … The question is whether Amgen is being hyper-cautious or whether the risk of suicidality is especially concerning.  Questions also emerge around the cause of risk – is this a spurious cluster of events unrelated to brodalumab; is suicidality perhaps related to relapse from the excellent efficacy associated with brodalumab after withdrawal (remember most patients exhibited at least PASI 90 on treatment but durability was very poor upon withdrawal); or perhaps suicidality is related to blocking the IL-17RA (note that suicidality has not to our knowledge been reported for the IL-17A ligand mAb Cosentyx) … One final point is whether regulators will now reevaluate suicide risk of IL-17 related molecules as a class – much greater clarity of brodalumab data is required to make a judgement.” That’s quite a nice summary from UpdatesPlus.

FierceBiotech’s report added “AstraZeneca would face some stiff competition if it decides to move forward solo on the drug. Novartis is already well in front with its IL-17 program for secukinumab, approved in January as Cosentyx. Eli Lilly has also been racking up positive late-stage studies for its IL-17-blocking ixekizumab, trailed by Merck’s MK-3222 and Johnson & Johnson’s IL-23 inhibitor guselkumab.”

Still, brodalumab demonstrated remarkable efficacy in psoriasis – Amgen and AstraZeneca went so for as to include a PASI100 score in one of their trials, meaning 100% clearance of psoriatic plaques, and the drug would have shown well against the best of breed, which today is likely Novartis’ anti-IL-17 antibody secukinumab. It is crowded space however, with antagonists targeting multiple nodes in the IL-17/IL-23 axis, alongside the biologics mentioned earlier.

Here is the current landscape from CiteLine (including brodalumab):

CiteLine

All in all, a tough crowd, and one that Amgen likely felt it could not face with a compromised label.

Let’s go back to the question posed above: bad luck, bad target or victim of superior efficacy? “Bad luck” suggests a statistical fluke in the data, potentially caused by the generally higher rates of suicidal tendencies observed in the moderate to severe psoriasis patient population. “Victim of superior efficacy” is in a sense a related issue, since the suggestion is that the loss of responsiveness to the drug, or a relapse, triggers a suicidal response as plaques return. Neither of these statements is really formulated as a hypothesis, and it doesn’t matter, as we don’t have the actual trial data yet with which to perform hypothesis testing.

“Bad target” is the most worrisome suggestion, and this can be formulated as a hypothesis, formally, the null hypothesis is that targeting the IL-17 receptor does not cause suicidal tendencies. Unfortunately, we still can’t test the hypothesis, and it seems likely that having the actual data won’t really help, that is, the study is probably not powered to reject that particular null hypothesis. So, what do we know? A few things, as it turns out.

First is that a link between the immune system and the nervous system is well established, although much of the focus has been on the role of neuronal enervation on immune responses. But clinically at least, the picture is muddier than that. High dose IL-2 can cause neurotoxicity, even hallucinations, according to Dr. Kathleen Mahoney, an oncologist at Beth Israel Deaconess and the Dana Farber. But what is really interesting is what else happens: “Some IL-2 treated patients can have odd dreams, really crazy dreams, and they last for weeks after treatment, long past the time when IL-2 would still be present in the body”, Dr. Mahoney said. Interferon alpha therapy is associated with pathological (severe) fatigue and also depressive symptoms that develop after 4–8 weeks of treatment. Of note, preventive treatment with anti-depressants, in particular serotonin reuptake inhibition attenuates IFN-alpha-associated symptoms of depression, anxiety, and neurotoxicity. Some researchers have suggested (controversially) that anti-TNF antibodies can control depression. Such anecdotal clinical observations suggest that we really do not yet understand the immune system connection to CNS activity.

On the other hand, antagonism of cytokine activity, and particularly of the cytokines IL-6, IL-17 and IL-23, has not been associated with neurological symptoms. For example the anti-IL-6 receptor antibody tocilizumab has shown a positive impact in rheumatoid arthritis patients quality of life scoring, which includes fatigue, anxiety, depression and a number of other factors. More to the point, the anti-IL-17 antibody secukinumab, that targets the IL-17 ligand (rather than the receptor), has not shown a link to suicide.

Clearly more data are needed, and it would not be surprising if the FDA began a drug class review if the data in the brodalumab trials warrant. They could cast quite a wide net given the complexity of this pathway, which overlaps with IL-6, IL-12 and IL-23. This casts a pall over the dermatology and particularly the rheumatology landscape, which is really waiting for novel therapeutics to move them successfully into new and important indications such as lupus and Type-1 Diabetes. The IL-17/IL-23 axis was to be that next great hope, and with luck we will still see these drugs moving out of their core indications of psoriasis and inflammatory bowel disease into new indications.

One last thing.

Those other antibodies – where are they now? A quick scorecard:

snapshot

It is readily seen that none of these are beyond early Phase 2, so it’s fair to say that the rest of the Amgen/AstraZeneca partnership has a long way to go. I, for one, wish the ongoing collaboration the very best of luck, particularly in the lupus indications, where we can really use some good news.

stay tuned.

Snow Day Reading: The New Multiple Myeloma Therapeutics

There was a comment floating around Twitter that “Biotech was boring this week” and that’s true, it has been a slow news week. Sanofi took the ax to about 100 Genzyme site staffers, Bayer and J&J announced R&D reorganizations, another CAR T cell deal got done (China) and IPOs and follow-on financings were announced: business as usual.

In the background though, slow but steady therapeutic advances are being made that will impact long-term company values. The development of antibody-based therapeutics in multiple myeloma (MM) is one nice example. Among the hematologic malignancies MM is a major disease. The incidence in the US is ~30K yearly and the prevalence is ~85K. A quick glance at that math reveals a disease with pretty short-term survival, less than 5 years according a report produced by the Leukemia & Lymphoma Society in 2014.

The age of onset for MM is 70 years old in the US, and this is important because it limits some treatment options for many patients who are physically frail. Such patients may not be candidates for high-dose chemotherapy and stem cell transplantation (SCT) and even patients who are given this first line regimen will eventually relapse. Those patients are served by second line therapeutics, described below.

The huge advance is this field has been the development of non-chemotherapeutic drugs. The IMiDs such as lenalidomide and pomalidomide (Revlimidtm and Pomalysttm, both from Celgene), are used with the proteasome inhibitors such as bortezomib (Velcadetm from Takeda) or carfilzomib (Kyprolistm, from Onyx) along with steroids (dexamethasone, prednisone) in various combinations. “Triplets” are the preferred therapeutic, as exemplified by the combination of lenalidomide, bortezomib and dexamethasone.

At the ASH conference in December a large retrospective outcomes study of newly diagnosed MM patients was presented (link 1). Here is some of the data from that study:

Cohort                                                                         % Probability of 3 yr Survival

All ages (N = 1444) 63
       < 65 70
       65 to < 75 65
       ≥ 75 47
SCT
      Yes 77
      No 54
Triplet therapy
     Yes 69
     No 55
IMWG risk
     High 59
     Standard 66
     Low 76
del(17p)
     Present 53
     Absent 63

So a few things here to note: age of onset is a negative factor for survival, in part due to the inability to get the majority of elderly patients to autologous stem cell transplantation (ASCT). In addition to age of diagnosis, the International Myeloma Working Group

(IMWG) risk score is a composite of factors that determine outcome, and finally the presence of a chromosome deletion (called del(17p)) is known to be associated with significantly shortened survival.

In this study they demonstrated further that the use of triplet therapy vs. non-triplet therapy was associated with significantly prolonged OS regardless of IMWG risk but no improvement was noted for triplet vs. non-triplet therapy in patients with del(17p). Two things are clear from this study – one, we have patient subsets that remains underserved (the elderly and those patients carrying del(17p), and two, triplet therapy is keeping 70% of patients alive for at least three years.

What about patients that fail triplet therapy and who relapse and or are refractory to further treatment (rrMM)? They fare very poorly indeed, as shown here:

                               newly diagnosed                                           treatment failures 

MM survival curves

There are a variety of novel therapeutics moving forward in rrMM, including novel proteosome inhibitors, HDAC inhibitors, nuclear export protein inhibitors and any others. One class of therapeutic gaining significant attention are the antibodies directed to the MM cells. These include the antibodies to CD38 and other MM-selective cell surface proteins.

The lead therapeutic among the anti-CD38 antibodies is daratumumab from Genmab in collaboration with Janssen. The deal included a US$55 million upfront payment, an $80 million equity stake in Genmab, and milestone payments adding up to $1.1 billion or more.Daratumumab is a huMAX CD38 mAb which kills CD38+ tumor cells via CDC and ADCC activity and antibody-dependent cellular phagocytosis (ADCP) by macrophages. Additional activity may be due to apoptosis upon secondary cross-linking and modulation of CD38 enzymatic function (see ASH 2014 abstract # 3474). Daratumumab received the FDA’s breakthrough therapy designation in May 2013 for treatment of rrMM (for patients failing 2 lines of therapy).

When combined with lenalidomide and dexamethasone (len/dex), daratumumab produced an overall response rate (ORR) of 75% in the phase I dose ranging clinical trial. The trial was designed to accommodate an expansion cohort dosed at the MTD (maximum tolerated dose) of 16mg/kg. In the expansion cohort the ORR was ~ 92%.

In a phase Ib study daratumumab was combined with various regimens:

Screen Shot 2015-02-14 at 11.51.52 AM

These efficacy numbers are startlingly good. What will be really impressive is the associated duraton of response (DOR) and overall survival (OS) data once the trial is mature. In early February preliminary results from another Phase II study were announced. The study, called MMY2002, is listed as NCT01985126 on clinical trials.gov    (link 2). This two-part study enrolled 124 rrMS patients who had received at least three prior lines of therapy, including both a proteasome inhibitor and an IMiD, or were double refractory to therapy with a proteasome inhibitor plus an IMiD. The primary objectives of the study were to define the optimal dose and dosing schedule, to determine the efficacy of two treatment regimens of daratumumab as measured by ORR, and to further characterize the safety of daratumumab as a single agent. Two doses of daratumumab were compared in part 1, at 8 mg/kg and 16 mg/kg. The expansion cohort (part 2) received the higher dose based on interim safety analysis of the initial dose comparison.

The ORR was 29.2% in the 16 mg/kg dosing group with a DOR of 7.4 months. We can expect additional data to be presented at a medical conference this year, perhaps ASCO or ESMO, and ASH or EHA. These data will support the breakthrough therapy designation for daratumumab in rrMM and may lead to a 2015 approval in this patient population, i.e. based on the phase II results.

Additional daratumumab trials include 5 phase III trials in MM, including a series of studies in newly diagnosed MM, therefore, as front-line therapy, and a phase II trial ((LYM2001) in hematological malignancies. The study will evaluate daratumumab monotherapy in three different types of NHL, diffuse large B-cell lymphoma (DLBCL), follicular lymphoma (FL) and mantle cell lymphoma (MCL).  The study is expected to start enrolling patients in 2015.

Sanofi Oncology is developing SAR650984 (SAR), is a human IgG1 antibody that targets CD38. TCD11863 (NCT01749969) is a phase Ib trial evaluating the combination of SAR with len/dex in rrMM: patients averaged six prior therapies. These prior therapies included the second line therapeutics lenalidomide (94%), pomalidomide (29%), bortezomib (94%), and carfilzomib (48%). Eighty four percent of patients were relapsed and refractory to a least one second line therapeutic. In the dose ranging phase, the highest SAR dose of 10mg/kg was well tolerated.

After a median 9 month follow up, the ORR was 58%, with a clinical benefit rate of 65%, including a 6% stringent complete response rate. In patients receiving the 10 mg/kg dose, the ORR was 63%. The median progression free survival (PFS) was 6.2 months for all evaluated patients but was not yet reached in patients who received fewer than three prior therapeutic regimens before entering the study.

Looking just at the 84% of who were relapsed and refractory to least one second line therapeutic, the ORR was 50%.

An interesting study presented at ASH in December suggested that Immunogenetic factors contributing to NK cell function influenced clinical activity in pts treated with SAR/LEN/Dex. Specifically, the presence of a high-affinity KIR3DL1, HLA-B Bw4-80Ile genotype was associated with high ORR and prolonged PFS. This suggests that the NK cell competency of the patient influences the ability of NK cells to become activated in the presence of tumor cells coated with SAR antibodies. This fascinating study (ASH 2014, Abstract # 2126) should stimulate investigation of mechanisms of NK cell activation that could be used in combination with SAR, assuming the presence of len/dex does not complicate the picture. There are additional clinical studies of SAR, listed here: link 3. These include a phase I/II study in hematologic malignancies.

In addition to daratumumab and SAR650984, Celgene and MorphoSys are collaborating on the development of the CD38 antibody MOR03087 (aka MOR202). This antibody is currently being investigated as monotherapy and in combination with len/dexamethasone or bor/dex in a phase I/II rrMM study (NCT01421186). The Morphosys licensing deal with Celgene included a $92M upfront, $60M equity investment and downstream milestones. Takeda is developing the anti-CD38 antibodies Ab79 and Ab19, currently in preclinical studies (link 4). Xencor has a CD3/CD38 bispecific program. The small private biotech Molecular Templates has an anti-CD38 antibody-drug conjugate program. There are likely other programs out there.

Elotizumab (ELO) from Bristol Myers Squibb targets a different MM antigen, SLAMF7 (aka CS-1). A presentation at ASH (abstract #2119) reported early results from a phase Ib study of ELO in combination with len/dex.ELO selectively kills SLAMF7-positive MM cells through both direct activation and engagement of NK cells. A multicenter, open-label, Phase Ib trial (NCT01393964) enrolled patients with newly diagnosed or rrMM and varying renal function. Renal function is a dose limiting feature of rrMM treatment and disease progression. ELO (10 mg/kg) plus len/dex was given in 28-day cycles until disease progression or unacceptable toxicity. 26 pts were treated, 8 with Normal Renal Function (NRF), 9 with Renal Insufficiency (RI), and 9 with End Stage Renal Disease (ESRD). 89% had received prior therapy (median 2 regimens). Prior bor, thalidomide, or len treatment occurred in 21 (81%), 11 (42%), and 9 (35%) patients, respectively. ORRs were 75% (NRF), 67% (SRI), and 56% (ESRD). Thirty-eight percent NRF, 56% of SRI, and 11% of ESRD patients had a very good partial response or better. Therefore ELO/len/dex was well tolerated and showed clinical responses in MM patients regardless of renal function.

These new therapeutics for MM will certainly complement the existing triple therapies, giving patients added hope and time. We certainly expect that one of the new combinations of antibodies and the second line “triple therapeutics” discussed above will have an even more dramatic impact on MM when given in the front-line setting.

In the meantime Janssen (J&J) and Genmab are poised to give Celgene some real competition in the MM space.

Immunotherapy: Companies Chasing Immune Checkpoint Therapeutics

Excitement continues to build in the Immunotherapeutic drug development space following a recent flurry of deals. In the most recent, we saw Novartis acquire Costim Pharma(http://www.fiercebiotech.com/story/novartis-beefs-its-cancer-immunotherapy-pipeline-biotech-buyout/2014-02-17).

The deal making begs the question as to what, and who, is next. The immunotherapeutic space is very large and diverse so it’s important to focus. Lets start by defining the space broadly, using the following categories:

1) Immune checkpoint modulators. These are therapeutics specifically designed to alter the way the immune system interacts with a tumor. This field is exemplified by the anti-CTLA4 antibody ipilimumab (Vervoytm), from Bristol Myers Squibb and the anti-PD-1 antibody MK-3475, from Merck.

2) Tumor depleting antibodies. These are antibodies with inherent or engineered cell-killing (cytotoxic) activity. The first generation of cytotoxic antibodies is best illustrated by the anti-CD20 antibody rituximab (Rituxantm) from Roche. Engineered antibodies have increased cytotoxic activity (ofatumumab from GlaxoSmithKline being an important example). Other formats include bispecific antibodies that recognize 2 different tumor proteins (antigens) simultaneously. All of these antibodies act by recruiting the immune system to kill cells that they have bound. The antibodies do this by activating cell killing NK and CD8+ T cells and by activating the complement cascade.

3) Bispecific antibodies and fusion proteins that recruit T cells, NK cells or dendritic cells and bind tumor antigen, simultaneously. These molecules function similarly to tumor depleting antibodies, but have the added activity of specifically engaging relevant immune cell types.

4) Modified T cells. Made famous by the CAR-T (CAR-19) technology developed by Carl June at U Penn, this technology uses genetic engineering to take a patients T cells and repurpose them for high impact tumor cell recognition and killing.

5) Cancer vaccines. Exemplified by Provengetm from Dendrion, these are techniques designed to induce an immune response to the tumor by immunizing with tumor antigens along with immune stimulants. There are ex vivo approaches (like Provenge) and in vivo approaches.

Note that we have left out the antibody-drug conjugates (ADC) and radiolabeled antibodies since they theoretically do not require the immune system to attack the tumors. In this class the cytotoxic drug or radioactive payload is brought to the tumor by the antibody.

Today we will only discuss novel and next generation therapeutics in the first class: immune checkpoint modulators.

The field has been dominated by discussion of the clinical stage drugs being developed to target the CTLA4 and PD-1 pathways. Blocking CTLA4 shuts down this T cell inhibitory pathway by preventing interaction of CTLA4 with it’s ligands, called CD80 and CD86, which are expressed on B cells, dendritic cells, macrophages and related cell types. This then allows these ligands to productively interact with the stimulatory receptor CD28, also expressed on T cells, thereby promoting T cell activation. In the case of the PD-1 pathway, blocking PD-1 or its ligand (PD-1L) prevents another inhibitory pathway on T cells, although in this case the ligand is often found overexpressed on tumor cells, that is, this is an active pathway for immune evasion.

Just for review, these are the key late stage clinical therapeutics:

drug

target

phase

company

 
     ipilimumab      CTLA4      approved      Bristol Myers Squibb
     nivolumab      PD-1      3      Bristol Myers Squibb
     MK-3475      PD-1      3      Merck
     MPDL3280A      PD-L1      3 (not yet recruiting)      Roche/Genentech

These are all monoclonal antibodies (mAbs). The approval and phase 3 designations refer to advanced metastatic melanoma however all of these drugs are in multiple clinical trials for many tumor types. Of equal interest are the ipilimumab/nivolumab co-therapy trials also underway.

So these are very advanced drugs. Earlier clinical trials with agents targeting the CTLA4 and PD-1 pathways are shown here:

drug

target

phase

company

       
     tremelimumab    CTLA4   1 and 2, in various solid     tumors      Astra Zeneca          (AZN)/Medimmune
     MEDI4736    PD-L1   1 and 1/2 in various solid   tumors      AZN/Medimmune
     pidilizumab    PD-1   2: hematological cancers,   solid tumors      CureTech Ltd
     BMS-9365569    PD-L1   1: multiple cancers      Bristol Myers Squibb
     AMP-224    PD-1   1: advanced cancers      Amplimmune/AZN
     AMP-514    PD-1   1: advanced cancers      Amplimmune/AZN

Again these earlier stage drugs are all mAbs, except AMP-224, a Fc-PD-L2 fusion protein that serves as a soluble inhibitor of PD-1. Pidilizumab had been partnered with Teva, but was returned last year. According to Nature Reviews Drug Discovery (NRDD), CureTech is seeking a partner for this drug to advance its’ development (http://www.nature.com/nrd/journal/v12/n7/full/nrd4066.html). The NRDD report is free to read and download.

There are other immune checkpoint modulators in the clinic, and we’ll get to those in a bit. What has been really shocking is how aggressive large pharma and biotech have been in acquiring very early stage assets in the immune checkpoint area. The CoStim acquisition by Novartis is an excellent example. CoStim had no clinical assets, and probably not even any IND-enabled assets, and yet was scooped up. Why? And importantly, who is next?

“Why” is a pretty interesting question, and translates into “What did they own?” The answer in the case of CoStim was that they owned patents on novel antibody inhibitors of PD-1 and PD-L1/PD-L2. Possibly of greater importance, they owned intellectual property (IP) portfolios covering new checkpoint pathways, notably the LAG-3 pathway and the TIM-3 pathway. We have no clinical data yet on either of these pathways, but preclinical tumor models, and the expression profile of these pathways, suggests very strongly that they will be critical for the prosecution of specific tumor types. Therein lies the value of buying early into the science. Bruce Booth writing on the role of Atlas Venture in the CoStim deal, has a great take on this on the LifeSci VC blog (http://lifescivc.com/2014/02/immuno-oncology-startup-costim-pharmaceuticals-acquired-by-novartis/).

So are there other CoStim Pharmas just waiting to be scooped up? The question is critical for biopharma portfolio gurus trying to peer into the future, and for stock investors wondering who to bet on. That second category, stock investors, will be looking for public companies or venture owned companies about to go public. The recent surge in biotech IPOs has helped bring plenty of candidates into public view.

Lets have a look around, but as an organizing principal, we’ll let the biology of tumor immune evasion and response lead the way.

We briefly mentioned the ligands for CTLA4 (CD80 and CD86) and for PD-1 (PD-L1 and PD-L2). These proteins are all related by protein sequence, and are members of the B7 protein family. The receptors for these ligands are also related and can be considered members of the CD28 protein family. Lets start with these, and line them up:

Screen Shot 2014-02-23 at 4.27.58 PM

This image is from Drew Pardoll’s excellent review in Nature Reviews Cancer. This paper is free to read and download, and can be found here:                       http://www.nature.com/nrc/journal/v12/n4/full/nrc3239.html. At the top you see the PD-1 and CTLA4 pathways and corresponding ligands – note here that an activating receptor for PD-L1 and PD-L2 is proposed, although none has been found yet. At the bottom we see some newer members of the B7 family, B7RP-1 (ICOS-L), B7-H3 and B7-H4. There are both stimulatory and inhibitory pathways proposed. Not surprisingly, there have been a number of development deals across this spectrum of targets.

Novartis. We’ve already mentioned the CoStim/Novartis deal, which purportedly includes PD-1 and PD-L1/2 assets and IP.

Merck. Merck took the biopharma world by surprise a few weeks ago by announcing a suite of partnerships for MK-3475 anti-PD-1 mAb. The stance is bold and aggressive and shows that Merck recognizes the importance of anticipating combination therapy clinical practice and developing MK-3475 accordingly. The company is capitalizing on the momentum behind MK-3475 that has accelerated with FDA breakthrough therapy designation (for advanced melanoma) in April of last year and an aggressive rolling submission drug application, which should be completed by mid-year.

Merck plans to run clinical studies of MK-3475 in combination with axitinib, Pfizer’s small molecule kinase inhibitor for renal cell carcinoma. This deal is similar to the one that Merck did with GlaxoSmithKline (GSK) in December 2013, to pair MK-3475 with GSK’s kinase inhibitor, pazopanib, also in advanced renal cell carcinoma.

In a combination immunotherapy effort, MK-3475 will be paired with PF-05082566, Pfizer’s agonist mAb to the 4-1BB receptor. We’ll discuss 4-1-BB and related pathways later, as this is an interesting area. The combo therapy will be tested in multiple cancer types. In a similar effort, Merck will partner with Incyte to pair MK-3475 with INCB24360, an indoleamine 2, 3-dioxygenase (IDO) inhibitor, in patients with advanced or metastatic cancers. IDO inhibitors are a very hot subject, which we will tackle below. Finally, in collaboration with Amgen, Merck will combine MK-3475 treatment with Amgen’s investigational oncolytic immunotherapy talimogene laherparepvec, in patients with previously untreated advanced melanoma.

Merck also signed on with Ablynx in a very interesting deal to develop nanobody therapeutics to immune checkpoint targets. Nanobodies are derived from camelid (camels, llamas, etc) antibodies and have some nice intrinsic properties (small size, good pharmacodynamics). Of interest, the Merck deal specifies bi- and tri-specific nanobodies targeting different proteins.

Servier. In another very recent deal (February 13, 2014), French pharmaceutical firm Pierre Fabre licensed a peptide therapeutic directed to PD-1 from Biotech company Aurigene. This new therapeutic is IND-enabled, but clinical development has not begun. Servier also acquired rights to Macrogenic’s anti-B7-H3 mAb MGA271 in December 2011. B7-H3 is overexpressed by a variety of solid tumors (prostate, pancreatic, melanoma, renal cell, ovarian, colorectal, gastric, bladder, and NSCLC). It has been hypothesized that B7-H3 expression by tunors is a mechanism of immune evasion, however, since the receptor in unknown this remains a hypothesis. So, although an anti-B7-H3 antibody may have biological impact on the tumor, Macrogenics is taking no chances, and has engineered MGA271 for optimized interaction with cytotoxic immune cells, including NK cells, macrophages and CD8+ T cells. MGA271 is currently in phase 1, in patients with B7-H3+, refractory neoplasms.

Astra Zeneca. In October of 2013, AZN/Medimmune announced that it had acquired Amplimmune, a privately held company developing immune checkpoint modulators for oncology. This preclinical company’s assets included AMP-224, the Fc-PD-L2 fusion protein mentioned earlier, and AMP-514, an anti-PD1 mAb. In December of 2013, Amplimmune registered its first clinical trial for AMP-514, a phase 1 in patients with advanced solid tumors. As discussed in a column by FierceBiotech’s John Carroll “the widely acknowledged area for differentiation will be combinations … mAbs (anti-CTLA4 tremelimumab, anti-PD1 AMP514,  OX40 agonist MEDI6469) and … targeted therapies … AZN is gearing up for combination trials with Iressa & tremelimumab … AZN’s purchase of Amplimmune gained it access to other … targets … likely including another attractive checkpoint antibody to B7-H4″. You can see the article here:                     http://www.fiercebiotech.com/story/can-astrazeneca-catch-leaders-cancer-immunotherapy/2013-10-03

Amplimmune’s discovery portfolio covers many B7 family members and their patent portfolio includes both agonist and antagonist assets and IP. Within the database-visible patents there are claims to fusion proteins and antibodies targeting PD-1, PD-L1/2. B7-H3, B7-H4, “B7-H5″, ICOS and ICOS-L.

Bayer Healthcare. Late to the party is Bayer, who to date has not made a big play in immune modulatory drugs. The company took a step forward perhaps in a deal with Compugen (NASDAQ: CGEN), paying 10MM USD upfront in a collaboration/licensing agreement. The goal is to develop novel antibody based immune checkpoint regulators discovered by Compugen. While the company is secretive as to the specific targets, one may be TIGIT, a relatively new member immune regulatory protein with some very exciting preclinical biology.

Early stage assets like Compugen’s are hard to judge without the benefit of full due diligence. We can list some of the asset players however, and some are pretty easy to score just based on the prior reputation of the company:

-  Earlier this month Five Prime Therapeutics went on record as having novel ligands for B7-H3 and B7-H4 (http://www.biotech-now.org/business-and-investments/2014/02/bio-ceo-five-prime-therapeutics-company-snapshot#) among other targets. Five Prime has an antibody discovery and development deal with Adimab. As far as I can tell, none of these are visible in the patent databases to date. Five Prime recently went public (NASDAQ: FPRX).

-  Kadmon LLC, backed by the former head of Imclone, lists anti-PD-1 and anti-PD-L1 mAbs on its pipeline chart. However this company seems focused on other areas.

-  Locally, Third Rock funded Jounce Therapeutics is developing antibodies and proteins to undisclosed immune checkpoint targets. Jounce and Adimab have announced a collaboration to drive the antibody technology. It will of great interest to see if Jounce will take the IPO route over the next few years, or instead will be acquired while still private.

-  VISTA is another relatively new immune regulator being developed by privately held ImmuNext, in partnership with Johnson & Johnson.

-  In January of this year Johnson & Johnson’s Janssen unit agreed with BiocerOX Products to develop a new mAb to an immune checkpoint protein. The target was not released but is rumored to be PD-1.

-  By the way, J&J/Janssen really does seem to be taking a multi-pronged approach to get into this space. In late January J&J Innovation partnered with MD Anderson Cancer Center, as part of its “Moon Shots” oncology effort. The joint program will evaluate new combination therapies and identifying useful biomarkers for eight critical cancers. MD Anderson has a very similar agreement with Pfizer.

-  AnaptysBio, Inc has publicized a portfolio that includes an anti-PD-1 antibody, ANB011, and novel antibodies against other immune checkpoint receptors, including TIM-3 and LAG-3.

I’m going to assume that there are other CTLA4, PD-1, PD-L1 and PD-L2 assets out there in the hands of companies large and small. We’ll track the progress of these as they pop up, whether in the poster hall at AACR, or in press releases! Also, we will discuss companies targeting TIM-3 and LAG-3, along with 4-1BB, OX40, GITR, IDO, and various other interesting targets, next post.

 stay tuned.